Polyurethane from epoxy compound adduct

ABSTRACT

A polyurethane composition useful as a molding composition is prepared from (1) an adduct derived from the reaction product of a polyepoxide and a single epoxide reactive group-containing compound, or the reaction product of a monoglycidyl ether and an epoxide reactive groups-containing compound, (2) a polyisocyanate, and (3) optionally an isocyanate-reactive compound; wherein at least one of the adduct or polyisocyanate contains a rodlike mesogenic moiety.

BACKGROUND OF THE INVENTION

The present invention relates to poIyurethanes showing improved physicalproperties. In particular, it relates to polyurethanes in which physicalproperties are enhanced by molecular reinforcement.

Polyurethanes are a highly versatile class of plastics which find use ina broad range of applications. The properties of various polyurethanesin many cases determines, and often limits, these applications. Thus,much research is directed toward improving the properties of differenttypes of polyurethanes in order to better meet the needs of a specificend use. In particular, improvements in flexural strength/modulus,tensile strength, tear strength and moisture resistance are highlysought by those in the field.

One method of obtaining improvement in certain of the mechanicalproperties has been disclosed by Turner in U.S. Pat. No. 4,701,475. Thatpatent discloses polyurethanes containing dispersed particles of highmelting, rigid, rodlike polymer capable of increasing tensile strengthand/or elongation and, in some instances, tensile modulus. Thomas etal., in U.S. Pat. No. 4,745,137, discloses a solution or dispersion of apolymer prepared from an ethylenically unsaturated polyaromatic compoundwhich contains a rigid moiety comprising at least two aromatic nucleiwhich are connected by a rigid connecting group, in a compound having atleast two isocyanate-reactive groups per molecule. U.S. Pat. No.4,745,136 extends the scope of that invention to include solutions ordispersions of polymers prepared from ethylenically unsaturated steroidderivatives. Polyurethane slabstock foam prepared using the polymersolutions or dispersions exhibited improved indentation load deflection,modulus and tensile elongation. U.S. Pat. No. 4,745,135 disclosespolyurethanes prepared from polyols containing one or more mesogenicmoieties as a part of the backbone or as pendant groups. Exemplary arethe hydroxyl-terminated aromatic polyesters and the mesogen initiatedpolyethers such as alkylene oxide derivatives of cellulose or a rigid4,4'-bisphenol.

Tanaka et al. (Polymer Preprints, Japan, 33(7) 1647-50 (1984)) disclosesreaction of di(p-oxymethylphenyl)terephthalate or of abis(azomethine)diol, prepared via reaction of 1 mole of terephthaldehydeand 2 moles of p-aminophenethyl alcohol, with various diisocyanates toprovide liquid crystalline polyurethanes. Tanaka and Nakaya (KohunshiRonbunshu, 43(5) 311-314 (May 1986)) disclose reaction of4,4'-di(2-hydroxyethyloxy)biphenyl with various diisocyanates to provideliquid crystalline polyurethanes. Iimura et al. (Makromol. Chem. 182,2569-75 (1981)) and Japanese Patent Application No. 55-56968 disclosereaction of 3,3-dimethyl-4,4'-diisocyanatobiphenyl with variousalkanediols to provide liquid crystalline polyurethanes. The reaction of3,3'-dimethyl-4,4'-diisocyanatobiphenyl with di-, tri- or tetraethyleneglycol was shown to produce non-mesomorphic (amorphous) polyurethanes.

One particular problem encountered in the polyurethanes discussed above,in which relatively substantial levels of mesogenic moieties are presentin the main chain of the polyurethane, is that they possess relativelyhigh melt (Tm) and isotropization (Ti) temperatures. These values exceedtypical polyurethane processing temperatures and, in some cases, evenabove the decomposition temperature of the urethane linkages. Thus, theyrepresent impractical formulation variations.

Thus, it would be desirable in the art to prepare polyurethanecompositions from formulations which are easily processed and which donot tend to decompose at processing temperatures. Furthermore, it wouldbe desirable to prepare polyurethane compositions exhibiting enhancedmechanical properties such as flexural strength/modulus, tensilestrength, tear strength and moisture resistance from such formulations.

SUMMARY OF THE INVENTION

Accordingly, the present invention provides novel polyurethanecompositions prepared by reacting (1) an epoxy resin adduct and (2) apolyisocyanate, at least one of which contains a rodlike mesogenicmoiety. The formulation optionally further comprises one or moreadditional isocyanate-reactive compounds.

The present invention further provides novel epoxy resin adductsprepared by reacting an epoxide with an epoxide-reactive compound, atleast one of which contains a rodlike mesogenic moiety.

The present invention provides polyurethane compositions having improvedmechanical properties, notably tear strength, tensile strength, flexuralstrength/modulus and moisture resistance. Because of the relatively lowmelting points of many of the rodlike mesogenic moiety containing epoxyresin adducts, standard polyurethane processing conditions andtemperatures can be readily used, thus avoiding decomposition of thepolyurethane products.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

According to one embodiment of the present invention, an epoxy resinadduct having at least one rodlike mesogenic moiety is employed. Thisadduct can be effectively prepared by reacting an epoxide with anepoxide-reactive compound, at least one of which contains a mesogenicmoiety. The epoxide can be either a polyepoxide or a monoepoxide. In thecase of a polyepoxide, the other compound contains on the average permolecule a single epoxide-reactive group, and at least one of thereactants contains a rodlike mesogenic moiety. In the case of amonoepoxide, the other compound preferably contains on the average permolecule at least two epoxide-reactive groups, and at least one of thereactants contains a rodlike mesogenic moiety.

Selections of the generalized starting materials to produce the epoxyresin adducts useful in the present invention determines the location ofthe rodlike mesogenic moieties in the final adduct. Rodlike mesogenicside chain, or "pendant", moieties result from reaction of a rodlikemesogenic monoepoxide with a mesogen-free epoxide-reactive compound.Rodlike mesogenic side chains also result from the reaction of amesogen-free polyepoxide with a rodlike mesogenic epoxide-reactivecompound Conversely, rodlike mesogenic moieties are present exclusivelyin the main chain of adducts prepared by reacting a mesogen-freemonoepoxide with a rodlike mesogenic epoxide-reactive compound, or arodlike mesogenic polyepoxide with a mesogen-free epoxide-reactivecompound. Finally, when both the epoxide and the epoxide-reactivecompound contain rodlike mesogenic moieties, the resulting adductcontains rodlike mesogenic moieties both in the main chain and in sidechains.

Suitable polyepoxides which can be employed herein include particularlyany epoxy-containing compound which contains an average of more than onevicinal epoxide group per molecule. The epoxide groups can be attachedto any oxygen, sulfur or nitrogen atom or the single bonded oxygen atomattached to the carbon atom of a --CO--O-- group in which said oxygen,sulfur or nitrogen atom or the carbon atom of the --CO--O-- group isattached to an aliphatic, aromatic or cyclaoliphatic hydrocarbon groupwhich hydrocarbon group can be substituted with any inert substituentincluding, but not limited to, halogen atoms, preferably chlorine orbromine, nitro groups and the like or such groups can be attached to theterminal carbon atoms of a compound containing an average of more thanone --(O--CHR^(a) CHR^(a))--_(t) group where each R^(a) is independentlyhydrogen or an alkyl or haloalkyl group, containing from 1 to about 2carbon atoms, with the proviso that only one R^(a) group can be ahaloalkyl group, and t has a value from 1 to about 100, preferably from1 to about 20, more preferably from 1 to about 10, most preferably from1 to about 5.

The polyepoxides suitable in certain embodiments of the presentinvention for preparing the adducts preferably contain an average of twoor more 1,2-epoxide groups per molecule. As already noted, thepolyepoxides can be either free of mesogenic moieties or contain rodlikemesogenic moieties, depending upon the selection of the epoxide-reactivecompound. Some examples of typical polyepoxides are represented by thefollowing formulas: ##STR1## wherein each A is independently a divalenthydrocarbyl group having from 1 to about 20, preferably from 1 to about14, carbon atoms, a direct single bond, --O--, --CO--, --SO--, --SO₂ --,--S--, --S--S--, --CH¹ ═CHR¹ --, --C═C--, --N═N--, --CR¹ ═N--,--O--CO--, --NR¹ --CO--, --CR¹ ═N--N═CR¹ --, --CR¹ ═CR¹ --CO--, --N═CR¹--, --CO--O--, --CO--NR¹ --, --CO--CR¹ ═CR¹ --, --CO--O--N═CR¹ --, --CR¹═N--O--OC--, --CO--NR¹ --NR¹ --OC--, --CR¹ ═CR¹ --O--OC--, --CO--O--CR¹═CR¹ --, --O--OC--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--, -- CHR¹--O--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--CHR¹ --, --CHR¹ --CO--O--CR¹═CR¹ --, --CR¹ ═CR¹ --O--CO--CHR¹ --, --CO--S--, --S--OC--, --CH₂ --CH₂--CO--O--, --O--OC--CH₂ --CH₂ --, --C═C--C═C--, --CR¹ ═CR¹ --CR¹ ═CR¹--, ##STR2## each A¹ is independently a divalent hydrocarbyl grouphaving from 1 to about 10, preferably from 1 to about 4, carbon atoms;each A¹ is independently a ##STR3## each R is independently hydrogen ora hydrocarbyl or hydrocarbyloxy group having from 1 to about 10,preferably 1 to about 4, carbon atoms, a halogen atom, preferablychlorine or bromine, a nitro group, a nitrile group, a phenyl group or a--CO--R¹ group; each R¹ is independently hydrogen or a hydrocarbyl grouphaving 1 to about 3 carbon atoms; each R² is independently hydrogen or ahydrocarbyl group having from 1 to about 10, preferably from 1 to about3, carbon atoms, a halogen atom, preferably chlorine or bromine; m has avalue from about 0.001 to about 6, preferably from about 0.01 to about3; n has a value of zero or one; p has a value from zero to about 30.preferably from zero to about 5; and p¹ has a value from 1 to about 30,preferably from 1 to about 3. The aromatic rings can also contain one ormore heteroatoms selected from nitrogen, oxygen, sulfur, mixturesthereof and the like.

The term "hydrocarbyl" as employed hereinabove means any aliphatic,cycloaliphatic, aromatic, aryl substituted aliphatic or cycloaliphatic,or aliphatic or cycloaliphatic substituted aromatic groups. Thealiphatic or cycloaliphatic groups can be saturated or unsaturated. Whenapplied to the A group of Formulas II and V or the A' group of formulaVI, the hydrocarbyl group can also contain one or more heteroatomsselected from nitrogen, oxygen, sulfur, mixtures thereof and the like.The term "hydrocarbyloxy" as employed hereinabove means a hydrocarbylgroup having an oxygen linkage between it and the carbon atom to whichit is attached.

Specific examples of polyepoxides which can be used to prepare theadducts, and which are free of mesogenic moieties, include for examplethe diglycidyl ethers of resorcinol, bisphenol A,4,4'-dihydroxydiphenylmethane, 3,3',5,5'-tetrabromobisphenol A,4,4'-thiodiphenol, 4,4'-sulfonyldiphenol, 4,4'-dihydroxydiphenyl oxide,3-phenylbisphenol A, 3,3',5,5'-tetrachlorobisphenol A,3,3'-dimethoxybisphenol A; the triglycidyl ether oftris(hydroxyphenyl)methane; the polyglycidyl ether of a phenol orsubstituted phenolaldehyde condensation product (novolac); thepolyglycidyl ether of a dicyclopentadiene or an oligomer thereof andphenol condensation product; the advancement reaction products of theaforesaid di- and polyglycidyl ethers with aromatic di- or polyhydroxyl-or carboxylic acid- containing compounds including, for example,bisphenol A (4,4'-isopropylidenediphenol), o-, m-, p-dihydroxybenzene,2,4-dimethylresorcinol, 4-chlororesorcinol, tetramethylhydroquinone,1,1-bis(4-hydroxyphenyl)ethane, bis(4,4'-dihydroxyphenyl)methane,4,4'-dihydroxydiphenyl ether, 3,3',5,5'-tetramethyldihydroxydiphenylether, 3,3',5,5'-dichlorodihydroxydiphenyl ether,4,4'-bis(p-hydroxyphenyl isopropyl)diphenyl ether,4,4'-bis(p-hydroxyphenoxy)benzene, 4,4'-bis(p-hydroxyphenoxy) diphenylether, 4,4'-bis(4(4-hydroxyphenoxy)phenyl sulfone)diphenyl ether,4,4'-dihydroxydiphenyl sulfone, 4,4'-dihydroxydiphenyl sulfide,4,4'-dihydroxydiphenyl disulfide, 2,2'-dihydroxydiphenyl sulfone,4,4'-dihydroxydiphenyl methane, 1,1-bis(p-hydroxyphenyl)cyclohexane,4,4'-dihydroxybenzophenone, phloroglucinol, pyrogallol,2,2',5,5'-tetrahydroxydiphenyl sulfone, tris(hydroxyphenyl)methane,dicyclopentadiene diphenol, tricyclopentadiene diphenol; mixturesthereof; and the like.

In other embodiments of the present invention the polyepoxides used toprepare the epoxy resin adducts contain at least one rodlike mesogenicmoiety. "Mesogenic moiety", or "mesogen", as used in the presentinvention refers to one or more rigid rodlike structural units whichhave been found to favor the formation of liquid crystal phases in thecase of low molar mass substances. Thus the mesogen or rodlike mesogenicmoiety is that structure responsible for molecular ordering. Specificmesogens include an aromatic ring pair connected by a rigid centrallinkage. These aromatic rings are para substituted in relation to eachother and to the remainder of the compound in which they are present.The para substitution insures the highest aspect ratio. The aromaticrings are preferably bridged by a group selected from the following: adirect single bond, ----C.tbd.C--, --CR¹ ═N--, --N═N--, --O--CO--, --NR¹--CO--, --CR¹ ═N--N═CR¹, --CR¹ ═CR¹ --CO--, --CR¹ ═CR¹ --, --N═CR¹ --,-- CO--O--, --CO--NR¹ --, --CO--CR¹ ═CR¹ --, --CO--O--N═CR¹ --, --CR¹═N--O--OC--, --CO--NR¹ --NR¹ --OC--, --CR¹ ═CR¹ --O--OC--, --CO--O--CR¹═CR¹ --, --O--OC--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--, --CHR¹ --O--CO--CR¹═CR¹ --, --CR¹ ═CR¹ --CO--O--CHR¹ --, --CHR¹ --CO--O--CR¹ ═CR¹ --, --CR¹═CR¹ --O--CO--CHR¹ --, --CO--S--, --S--OC--, --CH₂ --CH₂ --CO--O--,--O--OC--CH₂ --CH₂ --, --C.tbd.C--C.tbd.C--, --CR¹ ═CR¹ --CR¹ ═CR¹ --,##STR4## group and n, A¹ and R¹ are as hereinbefore described.

The rodlike mesogenic moiety or moieties are connected with theremainder of the compound by means of glycidyl ether linkages ##STR5##which are present when p has a value greater than zero. The epoxy resinscontaining a rodlike mesogenic moiety which can particularly be employedherein include those represented by the aforementioned Formulas II, Vand VI, wherein at least about 80 percent of the molecules are parasubstituted by both the bridging groups (--A--) and by the glycidylether and hydroxyalkylidene linkages which are present when p has avalue greater than zero. For Formula VI the para substitution is withrespect to the direct bond between the aromatic rings. To optimize theaspect ratio, it is preferred that the aromatic ring substituents (R inFormulas II, V and VI) are hydrogen or methyl groups.

Representative polyepoxide compounds containing a rodlike mesogenicmoiety include, for example, the diglycidyl ethers of4,4'-dihydroxybiphenyl, 4,4'-dihydroxystilbene,4,4'-dihydroxydiphenylacetylene, 4,4'-dihydroxydiphenylazomethine,4,4'-dihydroxyazobenzene, 4,4'-dihydroxyazoxybenzene,4,4'-bis((4-hydroxy)phenoxy)diphenyl,3,3',5,5'-tetramethyl-4-4'-dihydroxydiphenyl,3,3',5,5'-tetrachloro-4,4'-dihydroxydiphenyl,2,2',6,6'-tetramethyl-4,4'-dihydroxydiphenyl, 4,4'-dihydroxybenzanilide,4'-hydroxyphenyl-4-hydroxybenzoate, 4,4'-dihydroxy-alpha-methylstilbene,4,4'-dihydroxy-alpha-cyanostilbene, the diglycidyl ethers of thedihydric phenols represented by the following formulas: ##STR6## whereinn' has a value from 1 to about 10. Also suitable are the productsresulting from advancing the aforementioned diglycidyl ethers witharomatic dihydroxyl or carboxylic acid containing compounds including,for example, all of the previously listed diphenol precursors to thediglycidyl ethers containing a mesogenic moiety; mixtures thereof andthe like.

To prepare the polyepoxides useful for preparing the epoxy resin adductsof the present invention, epoxidation of di- and polyhydroxy aromaticcompounds (or di- and polycarboxylic acids) can be performed by theknown methods described in, for example, Handbook of Epoxy Resins by Leeand Neville, McGraw-Hill, 1967; Jpn. Kokai Tokkyo Koho JP 62 86,484 (8796,484); EP 88-008358/92; and Journal of Applied Polymer Science, Vol.23, 1355-1372 (1972), all of which are incorporated herein by reference.This usually includes reacting the respective di- or polyhydroxyaromatic compound (or di- and polycarboxylic acids) with anepihalohydrin such as, for example, epichlorohydrin or methylepichlorohydrin, followed by dehydrohalogenation with a basic-actingmaterial such as, for example, an alkali metal hydroxide, typicallysodium hydroxide, and finally recovery of the resulting glycidyl ether(or ester) product. For the production of polyepoxides from di- andpolyhydroxy aromatic compounds possessing functional groups or linkagesthat are sensitive to hydrolysis under the reaction conditions employedin certain epoxidation chemistries, alternate techniques of preparationcan be employed. For example, Japanese Patents 58-206579 and 63-010617teach preparation of the diglycidyl ether of the bisphenol representedby the following formula ##STR7## which is a compound containingazomethine linkages known to be sensitive to hydrolysis. It is alsopossible to perform an anhydrous epoxidation including azeotropicremoving the water and epichlorohydrin from a reaction mixtureconsisting of epichlorohydrin, a diphenol, a phase transfer catalystsuch as, for example, benzyltrimethylammonium chloride, and, optionally,one or more solvents while adding aqueous sodium hydroxide. Thisanhydrous epoxidation is preferably conducted under a vacuum.Alternatively non-aqueous sodium hydroxide can be used. In order tocontrol reaction exotherm, the solid sodium hydroxide is typically addedto the epoxidation reaction mixture in aliquots as a powder. A typicalanhydrous epoxidation technique is described in U.S. Pat. No. 4,499,255,which is incorporated herein by reference in its entirety. The anhydrousepoxidation of 4'-hydroxyphenyl-4-hydroxybenzoate, a compound containinga hydrolytically sensitive ester linkage is taught in U.S. Pat. No.4,762,901, which is incorporated herein by reference in its entirety.

Another method of preparing the polyepoxides useful for preparing theepoxy resin adducts of the present invention is advancement reaction ofdi- and polyglycidyl ethers with di- and polyhydroxy aromatic compounds(or di- and polycarboxylic acids). Advancement is described in, forexample, the aforementioned Handbook of Epoxy Resins, and is generallyknown to those skilled in the art. The advancement generally involvesmixing and heating the di- or polyhydroxy aromatic compound (or di- andpolycarboxylic acid) and the di- or polyglycidyl ether. A catalyst suchas, for example, ethyltriphenylphosphonium acetate.acetic acid complex,tetrabutylphosphonium bromide, tetrabutylammonium bromide orbenzyltrimethylammonium chloride, is preferably added to facilitate theadvancement reaction. Suitable advancement catalysts include, forexample, those disclosed in U.S. Pat. Nos. 3,306,872; 3,341,580;3,379,684; 3,477,990; 3,547,881; 3,637,590; 3,843,605; 3,948,855;3,956,237; 4,048,141; 4,093,650; 4,131,633; 4,132,706; 4,171,420; and4,177,216; which are incorporated herein by reference.

For the production of advanced polyepoxides using di- or polyhydroxyaromatic compounds which are of low solubility in the di- orpolyglycidyl ether reactant or which possess relatively high meltingpoints, one or more solvents are preferably added to the advancementreaction mixture. Care should be taken to utilize only those solventswhich are inert to reaction with any of the reactants or the epoxideproduct. Advancement reaction of the di- or polyglycidyl ethers can alsobe performed using primary monoamines, bis(secondary diamines), oraromatic di- or polythiol compounds.

Suitable aromatic di- and polyhydroxyl containing compounds which can bereacted with the di- or polyepoxides to prepare advanced polyepoxidesinclude, for example, those represented by the Formulas I, II, IV, V orVI above, wherein p has a value of zero and the glycidyl ether groupsare replaced with hydroxyl groups. Particularly suitable di- orpolyhydroxyl containing compounds include, for example, resorcinol,catechol, hydroquinone, bisphenol A, 4,4'-dihydroxydiphenylmethane,3,3',5,5'-tetrabromobisphenol A, 4,4'-thiodiphenol,4,4'-sulfonyldiphenol, 4,4'-dihydroxydiphenyl oxide, 3-phenylbisphenolA, 3,3'5,5'-tetrachlorobisphenol A, 3,3'-dimethoxybisphenol A,4,4'-dihydroxybiphenyl, 4,4'-dihydroxystilbene,4,4'-dihydroxydiphenylacetylene, 4,4'-dihydroxybenzanilide,4,4'-dihydroxy-α-methyl-stilbene, 4,4'-dihydroxydiphenylazomethine,4,4'-dihydroxyazobenzene, 4,4'-dihydroxyazoxybenzene,4,4'-bis((4-hydroxy)phenoxy)diphenyl,3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl,3,3',5,5'-tetrachloro-4,4'-dihydroxydiphenyl,2,2',6,6'-tetramethyl-4,4'-dihydroxybiphenyl, 4,4'-dihydroxychalcone,4,4'-dihydroxy-c-cyanostilbene, 4,4'-dihydroxyphenylbenzoate, mixturesthereof and the like.

Suitable di- and polycarboxylic acids which can also be used to prepareadvanced epoxides include, for example, 1,4-cyclohexane dicarboxylicacid, 4,4'-dicarboxybiphenyl, 4,4'-dicarboxy-α-methylstilbene,4,4'-dicarboxydiphenylacetylene, 4,4'-dicarboxystilbene,4,4'-dicarboxydiphenylazomethine, 4,4'-dicarboxydiphenylmethane,4,4'-dicarboxydiphenyl oxide, 4,4'-dicarboxydiphenyl sulfide,4,4'-dicarboxydiphenyl sulfone, 1,4-benzenedicarboxylic acid, mixturesthereof and the like.

Preferably the advancement reaction is carried out at a temperature offrom about 25° C. to about 250° C., more preferably from about 60° C. toabout 200° C. Reaction times from about 15 minutes to about 24 hours arepreferred, with from about 30 minutes to about 4 hours being morepreferred.

Suitable monoepoxide compounds containing one or more rodlike mesogenicmoieties, which are useful in the preparation of the epoxy resin adductscontaining rodlike mesogenic moieties, are prepared using conventionalchemistry that is well known in the art. These compounds preferablycontain an average of about one 1,2-epoxide group per molecule. In oneembodiment of the present invention the monoepoxides can be prepared byreacting a compound containing an average of one epoxide-reactive groupper molecule with an epihalohydrin, such as epichlorohydrin. Followingreaction the product is dehydrohalogenated using a basic-actingmaterial, such as an alkali metal hydroxide, and then the monoglycidylether product is recovered. The compound containing an average of oneepoxide-reactive group per molecule can also contain one or more rodlikemesogenic moieties. For the production of monoepoxides possessingfunctional groups or linkages that are sensitive to hydrolysis under thereaction conditions employed in certain epoxidation chemistries,alternate techniques of preparation such as are previously described forthe polyepoxides can be employed.

Suitable monoepoxide compounds which are free of mesogenic moietiesinclude, for example, the aliphatic, cycloaliphatic and aromaticmonoglycidyl ethers such as, for example, butyl glycidyl ether, phenylglycidyl ether, cresyl glycidyl ether, o-, m-, and p-methylphenylglycidyl ether, naphthyl glycidyl ether, cyclohexyl glycidyl ether, themonoglycidyl ester of benzoic acid, mixtures thereof and the like.

Suitable compounds containing an average of one group reactive with anepoxide group and one or more rodlike mesogenic moieties per moleculewhich can be reacted with epihalohydrin to provide the correspondingmonoepoxide are represented by the Formulas VII or VIII below: ##STR8##wherein Q is an epoxide-reactive group; M is a group containing two ormore aromatic rings bridged by a rigid central linkage; and R'0 is adivalent hydrocarbon group having from one to about 12 carbon atoms andmay be linear, branched, cyclic, aromatic or a combination thereof andmay be substituted with one or more inert groups, such as, for example,a methoxy group, or may contain one or more inert heteroatom containinglinkages, such as, for example, an ether linkage. Epoxide-reactivegroups represented by Q include --OH, --NHR", --SH, --COOH, and thelike. Typical rigid central linkage groups for bridging the aromaticrings include, for example, a direct bond, or a --CR¹ ═CR¹ --,--C.tbd.C--, --N═N--, --CR¹ ═N--, --CR¹ ═N--N═CR¹ --, --CR¹ ═CR¹ --CO--,--O--CO--, --NR¹ --CO--, --N═CR¹ --, --CO--O--, --CO--NR¹ --, --CO--CR¹═CR¹ --, -- CO--O--N═CR¹ --, --CR¹ ═N--O--OC--, --CO--NR¹ --NR¹ --OC--,--CR¹ ═CR¹ --O--OC--, --CO--O--CR¹ ═CR¹ --, --O--OC--CR¹ ═CR¹ --, --CR¹═CR¹ --CO--O--, --CHR¹ --O--CO--CR¹ ═CR¹ --, --CR¹ ═CR¹ --CO--O--CHR¹--, --CHR¹ --CO--O--CR¹ ═CR¹ --, --CR¹ ═CR¹ --O--CO--CHR¹ --, --CO--S--,--S--OC--, --CH₂ --CH₂ --CO--O--, --O--OC--CH₂ --CH₂ --,--C.tbd.C--C.tbd.C--, --CR¹ ═CR¹ --CR¹ ═CR¹ --, ##STR9## group and thelike; wherein each R¹ and A¹ are as hereinbefore defined and R" is adivalent hydrocarbon group which has from about 1 to about 20 carbonatoms and which can be linear, branched, cyclic, aromatic or acombination thereof. The rigid central linkage is required to bridge thearomatic rings to provide at least about 80 percent para substitution.The aromatic rings present in the M group can be inertly substituted;however, unsubstituted aromatic rings are preferred. The aromatic ringscan also contain one or more heteroatoms selected from nitrogen, oxygen,sulfur, mixtures thereof and the like.

This class of monoepoxide compounds containing rodlike mesogenicmoieties can be represented by the following Formulas IX or X ##STR10##wherein M, R¹, R' and R" are as previously defined and Q¹ is --O--,--NR"--, --S--, --CO--O--, and the like.

Representative of the compounds containing one or more rodlike mesogenicmoieties and a single epoxide-reactive group, which can be used toprepare the monoepoxides useful in the present invention, are, forexample, p-hydroxydiphenyl; p-N-methylaminodiphenyl;p-hydroxyphenylbenzoate; monomethylether of hydroquinone terephthalate;monomethylether of 4,4'-dihydroxydiphenyl; mono-n-butylether of4,4'-dihydroxydiphenyl; monomethylether of 4,4'-dihydroxystilbene;4(4-hydroxybenzoyl)benzoic acid; 4-phenylbenzoic acid; or thosecompounds represented by the following formulas ##STR11##

A second class of the monoepoxide compounds containing a rodlikemesogenic moiety include those which are typically prepared by theepoxidation of a compound containing an average of one epoxidizableolefinic unsaturated group per molecule and one or more mesogenicmoieties per molecule. Typical methods for preparing these monoepoxidecompounds include conversion of the olefin precursor to a chlorohydrinby hypochlorous acid treatment followed by dehydrochlorination of theresultant chlorohydrin intermediate thus formed; treatment of the olefinprecursor with one or more organic peracids (Prilezhaev Reaction) orperacid forming compounds such as, for example, perbenzoic acid,m-chloroperbenzoic acid, acetaldehyde monoperacetate, monoperphthalicacid, peracetic acid, performic acid, trifluoroperacetic acid and3,5-dinitroperoxybenzoic acid; and treatment of the olefin precursorwith one or more inorganic peracids such as, for example pertungsticacid. Details concerning these methods are taught in, for example, theaforementioned Handbook of Epoxy Resins, pages 3-1 to 3-24 (1967)published by McGraw-Hill, Inc.; D. Swern, Organic Reactions, volume 7,pages 378-433 (1953) published by John Wiley and Sons, Inc.; D. Swern,Organic Peroxides, volume 2, pages 355-533 (1971) published byWiley-Interscience; W. D. Emmons et al., Journal of the AmericanChemical Society 77, 89-92 (1955); and W. H. Rastetter et al., Journalof Organic Chemistry 43, 3163-3169 (1978). Alternative methods forpreparing these monoepoxide compounds include reaction of the olefinprecursor with oxygen or an alkyl peroxide, either directly or in thepresence of a catalyst consisting of a complex of vanadium, titanium,cobalt or molybdenum. Details concerning these methods are taught in,for example, T. Katsuki et al., Journal of the American Chemical Society102, 5974-5976 (1980); B. E. Rossiter et al., ibid. 103, 464-465 (1981);E. D. Mihelich et al., ibid. 103, 7690-7692 (1981); E. S. Gould et al.,ibid. 90, 4573-4579 (1960); H. J. Ledon et al., ibid. 103, 3601-3603(1981); L. D.-L. Lu et al., Journal of Organic Chemistry 49, 728-731(1984); and R. A. Budnik et al., ibid. 41, 1384-1389 (1976). As will berecognized by the skilled artisan, a number of additional olefinepoxidation techniques are available, notably the use of chromylcomplexes in direct olefin epoxidation as taught by N. Miyaura et al.,Journal of the American Chemical Society 105, 2368-23 (1983); the use ofa peroxysulfur intermediate in olefin epoxidation as taught by Y. H. Kimet al., Journal of Organic Chemistry 48, 1562-1564 (1983); the use oftungstate plus phosphate (arsenate) ions with hydrogen peroxide toepoxidize olefins as taught by C. Venturello et al., ibid. 48, 3831-3833(1983); ferric chloride activated hydrogen peroxide in olefinepoxidation as taught by H. Sugimoto et al., ibid. 50, 1784-1786 (1985);and olefin epoxidation using sodium hypochlorite andtetraphenylporphyrinatomanganese acetate as taught by M. E. DeCarvalhoet al., Tetrahedron Letters 24, 3621-3624 (1983). The aforementionedreferences are incorporated herein by reference.

When olefins are to be used as starting materials to prepare themonoepoxides of the present invention, rodlike mesogen-containingcompounds can preferably selected. These preferably contain an averageof one epoxidizable olefin group per molecule and are represented by theformula:

    M-(T).sub.n -(R').sub.n -Q'                                (XI)

wherein M, R¹, R' and R" are as hereinbefore defined; each nindependently has a value of zero or one; T is a divalent heteroatomselected from the group consisting of --O--, --NR"--, --S--, or--CO--O--; and Q' is an epoxidizable monoolefin group. The rigid centrallinkage groups for bridging the aromatic rings contained in M ispreferably substantially unreactive under the reaction conditions usedfor the epoxidation. Thus, typical rigid central linkage groups include,for example, a direct bond, --O--CO--, --NR¹ --CO--, --CO--O--,--CO--NR¹ --, --O--OC--CH₂ --CH₂ --, --CH₂ --CH₂ --CO--O--, --CO--NR¹--NR¹ --OC--, ##STR12## group and the like; and n, A¹ and R¹ are ashereinabove described.

The monoepoxides prepared from the rodlike mesogen-containing olefinstarting material can be represented by the following Formula XII

    M-(T).sub.n -(R').sub.n -Q.sup.2                           (XII)

wherein M, R' and T are as defined above and Q² is the epoxidized olefingroup such as, for example, ##STR13##

Suitable compounds containing one or more rodlike mesogenic moieties andan average of one epoxidizable olefinic unsaturated group per moleculeinclude, for example, those represented by the following formulas:##STR14## mixtures thereof and the like. Although it is not specificallyindicated by the monoolefin structural formulas above, many of thesynthetic methods can be used to provide optical activity (chirality) inthe resulting monoepoxides. This optical activity in the products of thepresent invention is especially desirable as a means of enhancing theirmolecular order.

Compounds containing a single epoxide-reactive group which can bereacted with a polyepoxide to prepare the epoxy resin adducts used inthe present invention include those containing at least one rodlikemesogenic moiety as shown in Formulas VII and VIII or those free ofrodlike mesogenic moieties as shown in Formula XIII:

    M.sup.1 -Q                                                 (XIII)

wherein M¹ is an aliphatic, cycloaliphatic or aromatic group and Q is ashereinbefore described, with the proviso that Q is not --OH when M¹ isan aliphatic or cycloaliphatic group.

Representative of the compounds containing a single epoxide reactivegroup that are free of mesogenic or moieties include the phenols, suchas, for example, phenol, o-, m- and p-methylphenol, o-, m- andp-nitrophenol, o-, m- and p-methoxyphenol, o-, m- and p-chlorophenol;the N-substituted compounds such as, methylaniline, N-ethylbutylamine;the thio compounds such as, for example, benzenethiol, cyclohexanethiol,hexanethiol; the carboxylic acids such as, for example, benzoic acid,4-methylbenzoic acid, naphthoic acid, cyclohexane carboxylic acid,hexanoic acid or any combination thereof and the like.

In another embodiment of the present invention a compound containing onthe average per molecule two or more epoxide-reactive groups can bereacted with a monoepoxide to prepare the epoxy resin adduct. Theepoxide-reactive compounds include those either free of or containing atleast one rodlike mesogenic moiety and can be represented by Formulas I,II, III, IV, V and VI above wherein p has a value of zero, each R³ isindependently hydrogen or a hydrocarbyl group having from 1 to about 12carbon atoms and the glycidyl ether groups are replaced with --OH,--NHR³, --SH or --COOH groups, or by Formula XIV:

    Q.sup.3 -M.sup.2 -Q.sup.3                                  (XIV)

wherein M² is an aliphatic or cycloaliphatic group and each Q³ isindependently NHR³, --SH or --COOH group.

Representative of the compounds containing on the average per moleculetwo or more epoxide-reactive groups are di- and polyphenols, in whichthe epoxide-reactive groups are hydroxyl groups. A number of these havebeen described above as being also suitable for use in the preparationof advanced polyepoxides.

Representative of the epoxide-reactive compounds which can be reactedwith a monoepoxide to prepare the epoxy resin adducts are thosecontaining on the average per molecule two or more --COOH groups. Theseinclude, for example, 1,4-cyclohexane dicarboxylic acid;4,4'-dicarboxybiphenyl; 4,4'-dicarboxy-α-methylstilbene;4,4'-dicarboxydiphenylacetylene; 4,4'-dicarboxystilbene;4,4'-dicarboxydiphenylazomethine; 4,4'-dicarboxydiphenylmethane;4,4'-dicarboxydiphenyl oxide; 4,4'-dicarboxydiphenyl sulfide4,4'-dicarboxydiphenyl sulfone; 1,4-benzenedicarboxylic acid; adipicacid; 1,4-cyclohexane dicarboxylic acid; and mixtures thereof. Thecarboxylic acid containing compounds can be used alone or incombination.

Representative of the epoxide-reactive compounds which can be reactedwith a monoepoxide to prepare the epoxy resin adducts are thosecontaining on the average per molecule two or more --NHR³ groups. Theseinclude, for example, o-, m-, and p-diaminobenzene;2,3,5,6-tetramethyl-1,4-diaminobenzene; 2,2-bis(4-aminophenyl)propane;2,2-bis(4-aminophenyl)ethane; 1,1-bis(4-aminophenyl)propane;4,4'-diaminodiphenylmethane; 2,2'-diaminodiphenyl; 4,4'-diaminodiphenyl;4,4'-diaminomethylstilbene; 4,4'-diaminostilbene;3,3',5,5'-tetramethyl-4,4'-diaminodiphenyl;3,3',5,5'-tetramethyl-4,4'-diaminophenyl;3,3',5,5'-tetrachloro-4,4'-diaminodiphenyl; 4,4'-diaminodiphenyl ether;4,4'-bis(4-aminophenoxy)diphenyl ether; 4,4'-diaminodiphenyl sulfone;4,4'-diaminodiphenyl disulfide;3,3',5,5'-tetraethyl-4,4'-diaminodiphenyl sulfone;1,1'-bis(4-aminophenyl)cyclohexane; bis-(2-amino-1-naphthyl) methane;4,4'-diaminobenzophenonone; 4,4'-diaminodiphenyl sulfide;3-phenyl-4,4'-diaminodiphenyl propane;3,3'-dimethoxy-4,4'-diaminodiphenyl propane;2,2',5,5'-tetraethyl-4,4'-diaminodiphenyl propane;2,2',5,5'-tetraaminodiphenyl sulfone; tris(aminophenyl)methane; anilineformaldehyde condensation products 1,6-hexanediamine; 1,4-diaminocyclohexane; and all types of secondary amine containingcompounds prepared by alkylation of the primary amine containingcompounds named above. The polyamine containing compounds can be usedalone or in combination.

Compounds containing on the average per molecule two or more --SH groupscan also be used to react with a monoepoxide to prepare the epoxy resinadducts of the present invention. These thiol-containing compoundsinclude, for example, o-, m-, and p-dimercaptobenzene;2,3,5,6-tetramethyl-1,4-dimercaptobenzene;2,2-bis(4-mercaptophenyl)propane; 2,2-bis(4-mercaptophenyl ethane;1,1-bis(4-mercaptophenyl)propane; 4,4'-dimercaptodiphenyl methane;2,2'-dimercaptodiphenyl; 4,4'-dimercaptodiphenyl;4,4'-dimercaptodimethylstilbene; 4,4'-dimercaptostilbene;4,4',6,6'-tetramethyl-4,4'-dimercaptodiphenyl;3,3',5,5'-tetrachloro-4,4'-dimercaptodiphenyl; 4,4'-dimercaptodiphenylether; 4,4'-bis(4-mercaptophenoxy)diphenyl ether;4,4'-dimercaptodiphenyl sulfone; 4,4'-dimercaptodiphenyl disulfide;3,3',5,5'-tetraethyl-4,4'-dimercaptodiphenyl sulfone;1,1'-bis(4-mercaptophenyl cyclohexane;bis-(2-mercapto-1-naphthyl)methane; 4,4'-dimercaptobenzophenone;4,4'-dimercaptodiphenyl sulfide; 3-phenyl-4,4'-dimercaptodiphenylpropane; 3,3'-dimethoxy-4,4'-dimercaptodiphenyl propane;3,3'-dimethoxy-4,4'-dimercaptodiphenyl propane;2,2',5,3'-tetramercaptodiphenyl sulfone; tris(mercaptophenyl)methane;1,6-hexanedithiol; 1,4-dithiocyclohexane; and mixtures thereof. Thepolythiol containing compounds can be used alone or in combination.

Once the monoepoxides, diepoxides or polyepoxides and epoxide-reactivecompounds as described above have been selected, epoxy resin adducts canbe prepared therefrom. Reaction conditions for forming these epoxy resinadducts, which contain at least one rodlike mesogenic moiety, varywidely, depending upon the type and amount of reactants employed; thetype and amount of catalyst(s) used, if any; the type and amount ofsolvent(s) used, if any; the mode of addition of the reactants employed;and other variables understood by those skilled in the art. The reactioncan be conducted at atmospheric, superatmospheric or subatmosphericpressures and preferably at temperatures of from about 0° C. to about260° C., more preferably from about 25° C. to about 220° C., and mostpreferably from about 50° C. to about 190° C. The time required tocomplete the reaction depends not only upon the variables, but also uponthe temperature. Higher temperatures require shorter periods of timewhereas lower temperatures require longer periods of time. Generally,however, times of from about 5 minutes to about 1 week, more preferablyfrom about 30 minutes to about 72 hours, most preferably from about 60minutes to about 48 hours are preferred.

A catalyst is optionally employed to prepare the epoxy resin adductscontaining one or more rodlike mesogenic moieties. Suitable catalystsinclude the phosphines, quaternary ammonium compounds, phosphoniumcompounds, sulfonium compounds, tertiary amines, mixtures thereof andthe like. The amount of catalyst used, if any, depends upon theparticular reactants and catalyst selection. However, preferably thecatalyst is used in amounts of from about 0.01 to about 3, preferablyfrom about 0.01 to about 1.5, most preferably from about 0.03 to about0.75 percent by weight, based upon the weight of the epoxy-containingcompound. Because the reaction of epoxide groups with amine orsubstituted amine groups is autocatalytic, an advancement catalyst isfrequently not required in this instance.

Particularly suitable catalysts are the quaternary phosphonium andammonium compounds such as, for example, ethyltriphenylphosphoniumbromide, -chloride, -iodide, -phosphate or -acetate;ethyltriphenylphophonium acetate.acetic acid complex;tetrabutylphosphonium bromide, -chloride, -iodide or -acetate;tetrabutylphosphonium acetate.acetic acid complex;butyltriphenylphosphonium tetrabromoisophenate;butyltriphenylphosphonium bisphenate; butyltriphenylphosphoniumbicarbonate; benzyltrimethylammonium chloride; tetramethylammoniumhydroxide; mixtures thereof; and the like.

It is also preferable to use one or more solvents inert in the epoxyresin adduct forming reaction of this embodiment of the presentinvention, especially when low solubility of a reactant containing arodlike mesogenic moiety is encountered. The use of a solvent canprovide for easier processing and recovery as well as an increased rateof conversion to the desired epoxy resin adduct product. The inertsolvent can be removed at the completion of the reaction usingconventional methods such as distillation, evaporation or vacuumstripping. Among the preferred solvents are the aliphatic ketones, suchas methylamyl ketone; the chlorinated hydrocarbons, such asperchloroethylene; and the aromatic hydrocarbons, such as chlorobenzeneand xylene.

The polyepoxide or monoepoxide and the epoxide-reactive compound(s) areemployed in proportions which provide an equivalent ratio, of epoxidegroups to epoxide-reactive groups, of from about 1:0.80 to about 1:1.25.More preferred is a ratio of from about 1:0.90 to about 1:1.05, and mostpreferred is from about 1:1. Purification or post reaction treatmentmethods such as, for example, recrystallization, chromatographicseparation, zone refining, crystal refining, wiping film distillation,vacuum distillation, solvent extraction, preferential chemicalderivatization/separation, combinations thereof and the like can beemployed to remove any stoichiometric excess of an unreacted reactantfrom the epoxy resin adduct product.

In reacting the epoxide and the epoxide-reactive compound(s) to form theepoxy resin adduct the order of addition is not critical. Thus, theepoxide and the epoxide-reactive compound(s) can be concurrently mixedtogether and subjected to the reaction conditions, or one component canbe added to the other component in increments up to and includingcontinuous addition. If increments are added, all or a part of an addedincrement can be allowed to react prior to addition of the nextincrement. However, when as a polyepoxide an advanced epoxy resin isselected, for example, from those represented by Formulas I, II, IV andVI wherein p has a value greater than zero, it may be desirable toprereact a part or all of the backbone hydroxyl groups formed as aconsequence of the advancement reaction. One method useful for theprereaction of backbone hydroxyl groups in advanced polyepoxides with anethylenically unsaturated ether, such as methyl isopropenyl ether, istaught by Perry in U.S. Pat. No. 3,804,795, which is incorporated hereinby reference. A second method useful for the prereaction of backbonehydroxyl groups in advanced epoxy resins with a trihalomethyl acylaromatic compound, such as trichloroacetophenone, is taught by Cavitt etal. in U.S. Pat. No. 4,575,543, which is incorporated herein byreference. A third method useful for the prereaction of backbonehydroxyl groups in advanced polyepoxides involves the use of one or moremonoisocyanate containing compounds. In this method, reaction conditionswhich form a urethane linkage via reaction of a hydroxyl and anisocyanate group are employed. Typical monoisocyanates include phenylisocyanate, 4-methylphenyl isocyanate, 2-methylphenyl isocyanate,cyclohexane isocyanate, dodecane isocyanate, mixtures thereof and thelike.

Prereaction of a part or all of the backbone hydroxy groups of anadvanced epoxy resin, prior to reaction with a compound containing asingle epoxide reactive group, reduces the number of hydroxyl groups inthe epoxy resin adduct product. The reduction of hydroxyl groups reducesthe number of reaction sites per molecule of epoxy resin adduct forsubsequent reaction with a polyisocyanate to form a polyurethaneproduct. Crosslink density is thus decreased and the mobility andaccessibility of the rodlike mesogenic moieties, resulting in enhancedcapability for molecular association, is increased.

The epoxy resin adduct formed by the reactions described above containsa mesogenic moiety and is reacted with a polyisocyanate to prepare thepolyurethanes of the present invention. Suitable polyisocyanates arewell known in the art and contain an average of more than one isocyanategroup per molecule. None, a part, or all of the polyisocyanatecomponent(s) used herein may contain one or more rodlike mesogenicmoieties. Isocyanate containing materials and their preparation aredescribed in, for example, the Encyclopedia of Chemical Technology,third edition, volume 13, pages 789-818, published by John Wiley andSons (1981), and by Siefken in Justus Leibegs Annalen der Chemie, 562,pages 75-136, both of which are incorporated herein by reference. Thus,any aliphatic, cycloaliphatic, polycycloaliphatic, aryl substitutedaliphatic, aromatic or heterocyclic polyisocyanates or prepolymers andoligomers thereof can be used herein. Typical of the polyisocyanatesuseful in the preparation of the polyurethanes of the present inventionare represented by the following formulas ##STR15## wherein A, A', R,R¹, R², m, n, p and M² are as hereinbefore described.

Representative of the polyisocyanates useful to prepare the compositionof the present invention which are free of mesogenic moieties include,for example, the following: 1,6-hexamethylene diisocyanate;1,4-cyclohexane diisocyanate; 1,3-cyclohexane diisocyanate;2,4-hexahydrotoluene diisocyanate; 2,6-hexahydrotoluene diisocyanate;perhydro-4,4'-diisocyanatodiphenyl methane;perhydro-2,4'-diisocyanatodiphenyl methane;perhydro-2,2'-diisocyanatodiphenyl methane;perhydro-3,3'-dimethyl-4,4'-diphenyldiisocyanate; 2,4-toluenediisocyanate; 2,6-toluene diisocyanate; 4,4'-diisocyanatodiphenylmethane; 2,4'-diisocyanatodiphenyl diisocyanate;2,2'-diisocyanatodiphenyl methane; 2,4'-diisocyanatodiphenyl methane;naphthalene-1,5-diisocyanate; 4,4'-diisocyanatotrimethyl cyclohexane;polyphenylene polymethylene polyisocyanate; mixtures thereof and thelike.

In preparing the polyurethane compositions of the present invention anepoxy resin adduct prepared as described above is reacted with apolyisocyanate, provided at least one of the reactants contains arodlike mesogenic moiety. Polyisocyanates containing a rodlike mesogenicmoiety which can be employed herein include, for example, thoserepresented by Formulas XVI and XIX above, wherein at least 80 percentof the molecules are para substituted by both the bridging groups(--A--) and the isocyanate groups (--N═C═O). For Formula XIX, the parasubstitution (at least 80 percent) is with respect to the direct bondbetween the aromatic rings. To optimize the aspect ratio of the rodlikemesogenic moiety, it is preferred that the aromatic ring substituents (Rin Formulas XVI and XIX) are hydrogen or methyl groups.

Representative polyisocyanates containing a rodlike mesogenic moietyinclude, for example, 4,4'-diisocyanatobiphenyl,3,3'-dimethyl-4,4'-diisocyanatodiphenyl,3,3',5,5'-tetramethyl-4,4'-diisocyanatodiphenyl;2,2',6,6'-tetramethyl-4,4'-diisocyanatodiphenyl;4,4'-diisocyanatostilbene; 4,4'-diisocyanatodiphenylacetylene;4,4'-diisocyanatoazobenzene; 4,4'-diisocyanatoazoxybenzene;4,4'-bis((4-isocyanato)phenoxy)diphenyl; 4,4-diisocyanatobenzanilide;4'-isocyanatophenyl-4-isocyanatobenzoate.;4,4'-diisocyanato-alpha-methylstilbene;4,4'-diisocyanato-alpha-cyanostilbene;4,4'-diisocyanato-alpha-ethylstilbene;4,4'-diisocyanatodiphenylazomethine, ##STR16##

Additional polyisocyanates which are useful to prepare the polyurethanecompositions of the present invention include polyisocyanates containingurethane groups such as, for example, the reaction product of toluenediisocyanate and trimethylolpropane described in the PolyurethaneHandbook, pages 77-79, published by Macmillan Publishing Co., Inc.(1985) or those described in U.S. Pat. No. 3,394,164, both of which areincorporated herein by reference; polyisocyanates containingcarbodiimide groups such as are described in U.S. Pat. No. 3,152,162 andby Ozaki in Chemical Reviews, 72, pp. 486-558 (1972), both of which areincorporated herein by reference; polyisocyanates containing allophanategroups such as are described in British Patent No. 994,890, BelgianPatent No. 761,626 and in the aforementioned Polyurethane Handbookreference, page 81, all of which are incorporated herein by reference;polyisocyanates containing isocyanurate groups such as are described inU.S. Pat. Nos. 3,001,973 and 3,154,522, German Patents Nos. 1,002,789,1,027,394 and 1,222,067 and in the aforementioned Polyurethane Handbookreference, pages 79-80, all of which are incorporated herein byreference; polyisocyanates containing urea groups such as are describedin the aforementioned Polyurethane Handbook reference, pages 81-82,which is incorporated herein by reference; polyisocyanates containingbiuret groups such as are described in U.S. Pat. Nos. 3,124,605 and3,201,372, British Patent No. 889,050, and in the aforementionedPolyurethane Handbook reference, page 82, all of which are incorporatedherein by reference; polyisocyanates containing acylated urea groupssuch as are described in German Patent No. 1,230,778, which isincorporated herein by reference; polyisocyanates containing estergroups such as are described in U.S. Pat. No. 3,567,763, British PatentNos. 965,474 and 1,072,956 and German Patent No. 1,231,688, all of whichare incorporated herein by reference; mixtures thereof and the like.

The commercially available isomeric mixtures of toluene diisocyanates,diisocyanatodiphenyl methanes and polyphenyl polymethylenepolyisocyanates, as well as the purified polyisocyanates, notably4,4'-diisocyanatodiphenyl methane, are preferred for use in preparingthe compositions of the present invention. Especially preferred aremixtures of either toluene diisocyanate or diisocyanatodiphenyl methanewith a lesser amount of a rodlike mesogenic polyisocyanate containingtwo or more aromatic rings bridged by a rigid central linkage of thetype hereinbefore described and wherein all substitutions on thearomatic rings are in the para positions. Thus, a blend of3,3'-dimethyl-4,4'-diisocyanatodiphenyl in 4,4'-diisocyanatodiphenylmethane is especially preferred.

In preparing the polyurethane materials of the present invention it isalso possible, and preferred, to incorporate one or more materialscontaining on the average two or more isocyanate-reactive hydrogens permolecule. It is especially preferred that all or a part of said materialcontaining two or more isocyanate reactive hydrogens per moleculesimultaneously contains at least one rodlike mesogenic moiety. This isin addition to the epoxy resin adduct which is, by definition, alsoisocyanate-reactive. Suitable materials can be selected from thewell-known classes of hydroxyl, amine and sulfhydryl containingmaterials. Typical examples of these materials are listed in theaforementioned Polyurethane Handbook, pages 42-60; in "Polyurethanes:Chemistry and Technology, Part I, Chemistry", High Polymers, volume XVI,pages 32-61, published by Interscience Publishers (1965); and inFlexible Urethane Foams Chemistry and Technology, pages 27-43, publishedby Applied Science Publishers (1982), all of which are incorporatedherein by reference. These materials include the polyether polyols;amine capped polyether polyols; hydroxyl containing polyesters;aliphatic hydroxyl containing polycarbonates; hydroxyl containingpolythioethers; hydroxyl containing polyolefins; hydroxyl containingurethanes and ureas prepared, for example, by the reaction of adiisocyanate and a stoichiometric excess of a diol, or by the reactionof a diisocyanate and a stoichiometric excess of a diamine,respectively; hydroxyl and/or amino containing polyesteramides; aminocontaining polyamides; alkanolamines; aliphatic, cycloaliphatic,polycycloaliphatic diols and polyols; polyamines; mercaptoalcohols;mercaptoamines; polymer modified polyols, i.e., containing vinyl polymeror copolymer grafted polyol, vinyl polymer or copolymer and unreactedpolyol; polyols containing dispersed polyurea particles, i.e.,polyharnstoff dispersion polyols; mixtures thereof; and the like.

Polyether polyols possessing average molecular weights of from about 250to about 6000 and from about 2 to about 8 hydroxyl groups are preferredmaterials containing on the average two or more isocyanate reactivehydrogens per molecule. Blends of these polyether polyols with aromaticdiamines or other known "chain extenders", such as, for example, with3,3'-dichloro-4,4'-diaminodiphenyl methane or4,4'-methylene-bis(3-chloro-2,6-diethylaniline), are also preferred.Also preferred are blends of these polyether polyols with rodlikemesogen containing aromatic diamines, such as, for example,3,3-dimethyl-4,4'-diaminodiphenyl.

In the general process of the present invention, an epoxy resin adductand a polyisocyanate, at least one of which contains a rodlike mesogenicmoiety, and optionally, one or more addition isocyanate-reactivematerials are combined in proportions which provide an equivalent ratioof isocyanate-reactive hydrogens to isocyanate groups of from about1:0.90 to about 1.0:1.25, preferably from about 1:0.95 to about 1.0:1.1,to provide the polyurethane compositions of the present invention. Thereaction may be performed in stages or increments or as a one-stepprocess. Suitable reaction conditions, reaction times, reactiontemperatures, and optional catalysts for preparation of the polyurethanecompositions of the present invention are well known to those skilled inthe art and are described in the aforementioned Polyurethanes: Chemistryand Technology reference, pages 129-217, and in the aforementionedEncyclopedia of Chemical Technology reference, pages 576-608, both ofwhich are incorporated herein by reference.

In a preferred process of the present invention, the epoxy resin adductis reacted with a stoichiometric excess of one or more polyisocyanatesto form an isocyanate terminated prepolymer. A preferred range of fromabout 2:1 to about 20:1, more preferably from about 2.5:1 to about 8:1,moles of isocyanate groups to moles of isocyanate reactive hydrogens isused. The additional isocyanate-reactive material, containing on theaverage at least two isocyanate-reactive groups per molecule, can alsobe incorporated in this prepolymer and is preferably combined with theepoxy resin adduct prior to reaction with the polyisocyanate. Theresultant product is an isocyanate terminated prepolymer containingexcess polyisocyanate which can be used as a material having more thanone isocyanate group per molecule for polyurethane forming reactions.

In another embodiment of the present invention, the epoxy resin adduct,alone or mixed with another isocyanate-reactive compound, is reactedwith substantially less than a stoichiometric amount of 1 or morepolyisocyanates to form a prepolymer terminated by active hydrogengroups such as hydroxyl groups. A preferred range of from about 0.05:1to about 0.60:1, more preferably from about 0.20:1 to about 0.50:1,moles of isocyanate groups to moles of isocyanate reactive hydrogens isemployed. The prepolymer product contains isocyanate reactive hydrogensand, as such, can then be reacted with a material having more than oneisocyanate group per molecule to form a polyurethane product.Alternately, the prepolymer can be reacted with a stoichiometric excessof a polyisocyanate as previously described to form another prepolymer,which in this case is isocyanate terminated. Many other processconfigurations can be used to prepare the polyurethane compositions ofthe present invention and will be readily apparent to the skilledartisan.

It is also possible to use one or more compounds which aremonofunctional (i.e., contain only one isocyanate reactive hydrogen permolecule) in reaction with an isocyanate group. These monofunctionalmaterials are chain terminating species in the polyurethane formingreaction. Preferably, these monofunctional compounds, if used, arepresent in an amount sufficient to react with from about 0.01 to about10 mole percent of the isocyanate groups. Examples of thesemonofunctional materials include, for example: aliphatic alcohols, suchas ethylene glycol monomethyl ether, octanol, 2-ethylhexanol; andmonoamines, such as dibutylamine, octodecylamine and aminocyclohexane.

In another embodiment of the present invention the epoxy resin adductcan also be prereacted, prior to use in the preparation of apolyurethane composition, to modify the type and/or number of hydroxylgroups present per molecule as well as its other properties, such asreactivity, solubility, melting point, viscosity and the like. Forexample, ethoxylation of the epoxy resin adduct converts secondaryaliphatic hydroxyl groups to primary aliphatic hydroxyl groups.Alkoxylation can also be used to incorporate a desired quantity ofaliphatic ether linkages to obtain certain property modifications.

Alternatively, reaction of the epoxy resin adduct with a compoundcontaining a single hydroxyl reactive group, such as, for example, amonoisocyanate can be used to reduce the number of hydroxyl groups permolecule available for subsequent reaction in polyurethane formingreactions. This chemistry is identical to that previously described, forprereaction of hydroxyl groups in advanced epoxy resins. Thus, areaction product of one equivalent of a trifunctional epoxy resin, suchas is shown in Formula IV where p equals zero, with three equivalents ofa compound containing a single epoxide reactive group, such as aphenolic hydroxyl group, and a single rodlike mesogenic moiety, such as,for example, a biphenyl group, provides a secondary aliphatic hydroxylcontaining triol. Reaction of one of the hydroxyl groups therein withphenyl isocyanate converts this triol to a secondary aliphatic hydroxylcontaining diol.

Certain of the polyurethane compositions of the present inventioncontain rodlike mesogenic groups as side chain (pendant) moieties. Thus,a polyurethane prepared from the diol resulting from the reaction ofp-phenylphenol with a diglycidyl ether of bisphenol A and4,4'-diisocyanatodiphenyl methane contains side chain diphenyl groupswhich are attached to the polymer chains via labile ether linkages, asshown: ##STR17##

The molecular association of these rodlike mesogenic biphenyl side chaingroups between polymer chains within the polyurethane matrix producesorientation in the soft segment phase (see, e.g., Example 2 in Table IIlof Example 8). This induced orientation in the soft segment phase of apolyurethane elastomer produced with a strain crystallizablepoly(ethylene oxide) block results in enhancement of tensile strengthand Die C tear strength, as well as reduced absorption of water (see,e.g., Example 19 in Table VII and Comparative Example 21 in Table VII).

Certain of the polyurethane compositions of the present invention canalso contain rodlike mesogenic moieties in the main chains, in additionto those present as side chain groups. These most preferred compositionscan be obtained (a) when all or a part of the polyisocyanate componentcontains one or more rodlike mesogenic moieties derived from two or morearomatic rings bridged by a rigid central linkage of the type describedabove: (b) when all or a part of the polyepoxide precursor to the epoxyresin adduct having at least one rodlike mesogenic moiety contains twoor more aromatic rings bridged by a rigid central linkage of the typehereinbefore described; or (c) when both (a) and (b) occursimultaneously. Thus, a polyurethane prepared from the diol resultingfrom the reaction of p-phenylphenol with a diglycidyl ether of4,4'-dihydroxydiphenyl and 4,4'-diisocyanatodiphenyl methane containsside chain diphenyl groups which are attached to the polymer chains vialabile ether linkages as well as diphenyl groups in the main chains, asshown; ##STR18##

Similarly, a polyurethane prepared from the diol resulting from thereaction of p-phenylphenol with a diglycidyl ether of bisphenol A and3,3'-dimethyl-4,4'-diphenyldiisocyanate contains side chain diphenylgroups which are attached to the polymer chains via labile etherlinkages as well as diphenyl groups in the main chains, as shown:##STR19##

The molecular association of at least a part of these rodlike mesogenicbiphenyl side chain groups with rodlike mesogenic biphenyl main chaingroups produces orientation in both the soft and hard segment phases(see, e.g., Example 4 in Table III of Example 8). This inducedorientation in the soft and hard segment phases of a polyurethaneelastomer produced with a strain crystallizable poly(ethylene oxide)block results in enhancement of flexural strength/modulus, Die C tearstrength and split tear strength, as well as reduced absorption of water(see, e.g., Example 20 in Table VII and Comparative Example 21 in TableVII).

Additional polyurethane compositions of the present invention whichcontain rodlike mesogenic moieties in the main chains in addition tothose present as side chain groups result from the use of a chainextender component, all or a part of which contains one or more rodlikemesogenic moieties. There most preferred composition can containadditional rodlike mesogenic moieties in the main chains via use of apolyisocyanate component containing one or more rodlike mesogenicmoieties and/or an epoxy resin adduct prepared from a polyepoxideprecursor having at least one rodlike mesogenic moiety.

Alternatively, one or more epoxy resin adducts free of mesogenicmoieties may be used to prepare polyurethanes of the present inventionprovided at least one other component used to prepare said polyurethanecontains at least one rodlike mesogenic moiety.

One advantage of the compositions of the present invention is thatmolecular association of rodlike mesogenic functionalities in thepolyurethane matrix provides molecular reinforcement manifested inenhanced mechanical properties. This reinforcement makes these materialsparticularly useful in applications requiring a higher degree ofmechanical strength than that of many other, conventional polyurethanematerials. The polyurethanes of the present invention can be made incellular (foamed) or non-cellular forms, and can contain additives andadjuvants which are used for well known purposes. For example, fillers,pigments, mold release agents, catalysts, blowing agents, surface activeagents, cell regulators, reaction retarding agents, stabilizers, flameretarding substances, plasticizers, fungistats, bacteriostats,emulsifiers, weathering and aging retardants, reinforcing materials,solvents, adhesion promoters and the like can be employed as customaryin the art. The compositions of the present invention are particularlyuseful in the preparation of elastomers, rigid and structural foams,flexible foams, reaction injection molded articles, moldings, coatings,castings and the like.

During processing prior to curing and/or during cure of the curablecompositions into a part, electric or magnetic fields or flow fields canbe applied for the purpose of enhancing the orientation of the rodlikemesogenic moieties contained or developed therein which in effectimproves the mechanical properties. As specific examples of thesemethods, Finkelmann et al, Macromol. Chem. 187, 2655-2662 (November1986). Magnetic field induced orientation of mesogenic main chaincontaining polymers has been demonstrated by Moore et al, ACS PolymericMaterial Sciences and Engineering, 52, 84-86 (April-May 1985). Magneticand electric field orientation of low molecular weight mesogeniccompounds is discussed by W. R. Krigbaum in Polymer Liquid Cyrstals,pages 275-309 (1982) published by Academic Press, Inc. All of the aboveare incorporated herein by reference in their entirety.

In addition to orientation by electric or magnetic fields, polymericmesophases can be oriented by drawing and/or shear forces which areinduced by flow through dies, orifices, and mold gates. A generaldiscussion for orientation of thermotropic liquid crystal polymers bythis method is given by S. K. Garg and S. Kenig in High ModulusPolymers, pages 71-103 (1988) published by Marcel Dekker, Inc. which isincorporated herein by reference. For the rodlike mesogen containingpolyurethanes based on the epoxy resin adducts, this shear orientationis preferably produced by processing methods such as reactive injectionmolding, extrusion, pultrusion, filming and the like.

The following examples are intended to be, and should be construed asbeing, illustrative only and are not limitative of the scope of thepresent invention in any way.

EXAMPLE 1 A. Preparation of an Epoxy Resin Adduct by the Reaction ofp-Phenylphenol and Diglycidyl Ether of Bisphenol A

p-Phenylphenol 170.20 grams, 1.00 hydroxyl equivalent) and a diglycidylether of bisphenol A (181.09 grams, 1.00 hydroxyl equivalent) having anepoxide equivalent weight (EEW) of 181.09 are added to a reactor andheated with stirring under a nitrogen atmosphere. Once a 90° C. reactiontemperature is achieved, ethyltriphenylphosphonium acetate.acetic acidcomplex (70 percent by weight in methanol) (0.3513 gram, 0.10 percent byweight) is added to the reactor and heating is continued. After sixteenminutes, the reaction temperature reaches 175° C. and this reactiontemperature is held for 174 minutes. The product is recovered as a lighttan colored solid of the following structure: ##STR20##

Epoxide titration reveals the product to contain 0.20 percent residualepoxide while hydroxyl titration reveals 4.948 percent hydroxyl.Infrared spectrophotometric analysis of a portion of the productconfirms the product structure (appearance of hydroxyl group absorbanceat 3408 cm⁻¹, disappearance of epoxide group absorbance). A portion ofthe product dissolved in chloroform is reacted with excess phenylisocyanate followed by rotary evaporation under vacuum to provide alight tan colored solid. Infrared spectrophotomeric analysis of filmsamples prepared from the reaction solution during the course of thereaction verifies the complete reaction of the hydroxyl groups of theproduct with the isocyanate groups (appearance of carbonyl groupabsorbance at 1737 cm⁻¹, disappearance of hydroxyl group absorbance).The phenyl isocyanate reaction product melts at approximately 80° C. toan isotropic fluid.

B. Synthesis of an Isocyanate Terminated Prepolymer Containing the EpoxyResin Adduct (7.21 weight percent) Prepared by Reacting p-Phenylphenoland Diglycidyl Ether of Bisphenol A

A portion of the reaction product of p-phenylphenol and diglycidyl etherof bisphenol A (72.14 grams, 7.21 weight percent) from A. above, apropylene glycol polypropoxylate having an average molecular weight of2000 (216.42 grams, 21.64 weight percent), a glycerine polyproxylatecapped with 18 percent ethylene oxide having an average molecular weightof 4850 (432.84 grams, 43.28 weight percent) and4,4'-diisocyanatodiphenyl methane (278.60 grams, 27.86 weight percent)are added to an oven dried glass reactor and heated with stirring to 80°C. under a dry nitrogen atmosphere. After two hours of reaction at the80° C. temperature, the transparent, light tan colored prepolymer liquidis recovered as a homogeneous solution and stored in a metal can under adry nitrogen atmosphere. Ninety six hours later, titration of portionsof the prepolymer reveals the presence of 6.955 percent isocyanate, ascompared with a theoretical isocyanate amount of 6.5 percent.

C. Preparation of a Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from B. above (400.2grams) is added to an oven dried glass reactor and heated with stirringto 50° C. under a vacuum. After 120 minutes of degassing the 50° C.prepolymer under a vacuum of 1 millimeter of Hg or less, the prepolymeris cooled to 28° C., stirring is stopped, the vacuum is released, and168.34 grams of a liquid chain extender solution are injected into thereactor.

The liquid chain extender solution is prepared by mixingmethylenebis(ortho-chloroaniline) (94.28 grams), propylene glycolpolypropoxylate having an average molecular weight of 2000 (56.56 grams)and glycerine polypropoxylate capped with 18 percent ethylene oxidehaving an average molecular weight of 4850 (84.84 grams) at 110° C. withstirring for 20 minutes followed by degassing at 50° C. under vacuum for30 minutes. Once the liquid chain extender solution is added, the vacuumis reestablished and vigorous mixing of the reaction mixture commences.After two minutes of mixing the reaction temperature has increased to36° C.

At this time stirring is again stopped, the vacuum is released, and 0.20milliliter of bismuth neodecanoate catalyst is injected into thereactor. Once the catalyst is been added, the vacuum is reestablishedand vigorous mixing of the reaction mixture commences. After one minuteof mixing, the reaction temperature has increased to 45° C. At this timestirring is stopped, the vacuum is released and the reactor contents arepoured into a pair of preheated (100° C.) 7.5 inch by 10.5 inch by 100mil aluminum molds. The molds are covered with steel covers and loadedinto a hydraulic press with platens preheated to 100° C. The pressure onthe molds in the press is increased to 1000 psi, released, and thenincreased to 10,000 psi. This pressure, concurrent with the 100° C.temperature is maintained for one hour. The molds are then removed andthe slightly opaque light tan colored polyurethane elastomer castingsare demolded and postcured for 16 hours at 100° C.

Physical and mechanical properties of the castings are tested and thetest results reported in Table I. Testing methods and conditions are asdescribed below:

1. Specific gravity of a pair of conditioned 1.5 gram samples isdetermined at 23° C.±2° C. using ASTM D 792 with the average valuereported in Table I.

2. Hardness is determined using a Shore A durometer at 23° C.±2° C. witha conditioned test piece as specified in ASTM D 2240.

3. Bashore rebound (resilience) is determined at 23° C.±2° C. withconditioned test pieces as specified in ASTM D 2632.

4. Die C tear strength is determined at 23° C.±2° C. using conditionedtest pieces (six) as specified in ASTM D 624.

5. Split tear strength is determined at 23° C.±2° C. using conditionedtest pieces (six) as specified in ASTM D 470.

6. Water absorption is determined at 23° C.±2° C. using both conditionedtest pieces (three) as well as predried test pieces (three) exposed todeionized water for one week. Predrying of the test pieces is completedin an oven maintained at 158° F. for sixteen hours prior to testing. Theaverage value of weight percent increase for each respective test isreported in Table I.

7. Compression set under constant deflection in air (Method B) isdetermined at 23° C.±2° C. using conditioned test pieces and an applied25 percent compression of the test pieces for 22 hours in accordancewith ASTM D 395 and is reported in Table I as a percentage of theoriginal thickness (Ct).

8. Flexural modulus is determined at 23° C.±2° C. using conditioned testpieces measuring one by three inches in accordance with ASTM D 790,Method I, Procedure B. The rate of crosshead motion is 0.5 inch perminute and a 2.0 inch span length is used.

9. Tensile properties are determined at 23° C.±2° C. using conditionedType IV test pieces in accordance with ASTM D 638. The speed of testingis 20 inches per minute. The results are collectively given in Table I.

EXAMPLE 2 A. Synthesis of an Isocyanate Terminated Prepolymer Containingan Epoxy Resin Adduct (14.13 weight percent) Prepared by Reactingp-Phenylphenol and of Diglycidyl Ether of Bisphenol A

A portion of the reaction product of p-phenylphenol and diglycidyl etherof bisphenol A (141.27 grams, 14.13 weight percent, prepared asdescribed in Example 1 above), a propylene glycol polypropoxylate havingan average molecular weight of 2000 (141.27 grams, 14.13 weightpercent), a glycerine polyproxylate capped with 18 percent ethyleneoxide having an average molecular weight of 4850 (423.80 grams, 42.38weight percent) and 4,4'-diisocyanatodiphenyl methane (293.66 grams.29.37 weight percent) are added to an oven dried glass reactor andheated with stirring to 80° C. under a dry nitrogen atmosphere. Aftertwo hours of reaction at the 80° C. temperature, the transparent, lighttan colored prepolymer liquid is recovered as a homogeneous solution andstored in a metal can under a dry nitrogen atmosphere. Twenty-two hourslater, titration of portions of the prepolymer reveals the presence of6.412 percent isocyanate, as compared with a theoretical isocyanateamount of 6.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (404.6grams) is added to an oven dried glass reactor and processed asdescribed in Example 1. A liquid chain extender solution (156.90 grams)is injected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (87.86 grams),propylene glycol polypropoxylate having an average molecular weight of2000 (52.72 grams) and glycerine polypropoxylate capped with 18 percentethylene oxide having an average molecular weight of 4850 (79.07 grams),as described in Example 1, including use of a bismuth neodecanoatecatalyst. Polyurethane elastomer castings are prepared as described inExample 1, and testing of their physical and mechanical properties isdone as described therein. The results are reported in Table I.

EXAMPLE 3 A. Preparation of an Epoxy Resin Adduct by the Reaction of4(4-Hydroxybenzoyl)benzoic Acid and Diglycidyl Ether of Bisphenol A

4(4-Hydroxybenzoyl)benzoic acid (72.67 grams, 0.30 carboxylic acidequivalent) and a diglycidyl ether of bisphenol A (54.33 grams, 0.30epoxide equivalent) having an epoxide equivalent weight (EEW) of 181.09and methylamyl ketone (40.0 grams) are added to a reactor and heatedwith stirring under a nitrogen atmosphere. Once a 90° C. reactiontemperature is achieved, ethyltriphenylphosphonium acetate.acetic acidcomplex (70 percent by weight in methanol) (0.127 gram, 0.10 percent byweight) is added to the reactor and heating is continued. After fifteenminutes the reaction temperature reaches 165° C. and this reactiontemperature is held for 315 minutes. The product is recovered and driedat 100° C. under vacuum to a constant weight to provide a lighttan-colored solid of the following structure: ##STR21## Epoxidetitration reveals the product to contain 0.03 percent residual epoxide.

B Synthesis of an Isocyanate Terminated Prepolymer Containing the EpoxyResin Adduct (7.25 weight percent) Prepared by the Reaction of4(4-Hydroxybenzoyl)benzoic Acid and Diglycidyl Ether of Bisphenol A

A portion of the reaction product of 4(4-hydroxybenzoyl)benzoic acid anda diglycidyl ether of bisphenol A (72.54 grams, 7.25 weight percent)from A. above, a propylene glycol polypropoxylate having an averagemolecular weight of 2000 (217.61 grams, 21.76 weight percent), aglycerine polypropoxylate capped with 18 percent ethylene oxide havingan average molecular weight of 4850 (435.22 grams, 43.52 weight percent)and 4,4'-diisocyanatodiphenyl methane (274.63 grams, 27.46 weightpercent) are reacted as described in Example 1. Titration of portions ofthe slightly opaque, light tan colored prepolymer reveals the presenceof 6.658 percent isocyanate, as compared with a theoretical isocyanateamount of 6.5 percent.

C. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from B. above (400.1grams) is added to an oven dried glass reactor and processed asdescribed in Example 1. A liquid chain extender solution (161.13 grams)is injected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (90.23 grams),propylene glycol polypropoxylate having an average molecular weight of2000 (54.14 grams) and glycerine polypropoxylate capped with 18 percentethylene oxide having an average molecular weight of 4850 (81.21 grams),as described in Example 1 including use of a bismuth neodecanoatecatalyst. Polyurethane elastomer castings are prepared as described inExample 1 and testing of their physical and mechanical properties isdone as described therein. The results are reported in Table 1.

EXAMPLE 4 A. Preparation of an Epoxy Resin Adduct by the Reaction ofp-Phenylphenol and Diglycidyl Ether of Bisphenol

p-Phenylphenol (170.20 grams, 1.00 hydroxyl equivalent) and a diglycidylether of bisphenol A (181.09 grams, 1.00 epoxide equivalent) having anepoxide equivalent weight (EEW) of 181.09 are used to prepare an epoxyresin adduct by the method shown in Example 1, except that the reactiontime at 175° C. is increased to 244 minutes. Epoxide titration revealsthe product to contain 0.07 percent residual epoxide.

B. Synthesis of an Isocyanate Terminated Prepolymer Containing the EpoxyResin Adduct (7.18 weight percent) Prepared by Reacting p-Phenylphenoland Diglycidyl Ether of Bisphenol A Plus Mesogenic Diisocyanate

A portion of the reaction product of p-phenylphenol and diglycidyl etherof bisphenol A (71.79 grams, 7.18 weight percent) from A. above, apropylene glycol polypropoxylate having an average molecular weight of2000 (215.37 grams, 21.54 weight percent), a glycerine polypropoxylatecapped with 18 percent ethylene oxide having an average molecular weightof 4850 (430.74 grams, 43.07 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (70.53 grams, 7.05 percent) and4,4'-diisocyanatodiphenyl methane (211.58 grams, 21.26 weight percent)are reacted as described in Example 1. Titration of portions of thetransparent, colorless prepolymer reveals the presence of 6.738 percentisocyanate, as compared with a theoretical isocyanate amount of 6.5percent.

C. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from B. above (400.1grams) is added to an oven dried glass reactor and processed asdescribed in Example 1. A liquid chain extender solution (163.06 grams)is injected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (91.31 grams),propylene glycol polypropoxylate having an average molecular weight of2000 (54.79 grams) and glycerine polypropoxylate capped with 18 percentethylene oxide having an average molecular weight of 4850 (82.18 grams)as described in Example 1 including use of bismuth neodecanoatecatalyst. Polyurethane elastomer castings are prepared as described inExample 1 and testing of their physical and mechanical properties isdone as described therein. The results are reported in Table I.

EXAMPLE 5 A. Preparation of an Epoxy Resin Adduct by the Reaction ofp-Phenylphenol and Diglycidyl Ether of 4,4'-Dihydroxybiphenyl

A diglycidyl ether of 4,4'-dihydroxybiphenyl (65.85 grams, 0.40 epoxideequivalent) having an epoxide equivalent weight (EEW) of 164.60,p-phenylphenol (68.08 grams, 0.40 hydroxyl equivalent) and methylamylketone (75.0 grams) are added to a reactor and heated with stirringunder a nitrogen atmosphere. Once a 90° C. reaction temperature isachieved, ethyltriphenylphosphonium acetate.acetic acid complex (70percent by weight in methanol) (0.134 gram, 0.10 percent weight) isadded to the reactor and heating is continued. After 10 minutes, thereaction temperature reaches 165° C. and a clear solution is observed.After 93 minutes at 165° C., the thick white slurry which is formed isdiluted with additional methylamyl ketone (75.0 grams). The reaction iscontinued at 160° C. as controlled by refluxing of methylamyl ketonesolvent. After 60 minutes at 160° C., the product slurry is recoveredand allowed to cool to a solid mass. After drying in a vacuum oven at110° C. for 24 hours, the product is recovered as a white solid (133.0grams) of the following structure: ##STR22## Epoxide titration revealsthe product to be free of residual epoxide. Gel permeationchromatographic analysis using glycerin polypropoxylates as calibrationstandards reveals a weight average molecular weight of 419 for theproduct, excluding a pair of minor shoulder peaks in the molecularweight calculation.

B. Evaluation of Liquid Crystallinity in the Epoxy Resin Adduct

A portion (0.0639 gram, 0.0002 hydroxyl equivalent) of the reactionproduct from A. above is dissolved in 1,4-dioxane (3.5 milliliters) thenphenyl isocyanate (0.0298 gram, 0.00025 mole) is added and the solutionheld at 80° C. under a dry nitrogen atmosphere for 48 hours. After thistime a hazy reaction mixture is recovered and the solvent is removedunder vacuum and at a temperature of 80° C. for 24 hours. The resultingurethane of the p-phenylphenol and diglycidyl ether of4,4'-dihydroxybiphenyl reaction product is recovered as a whitecrystalline solid. Optical microscopy under crosspolarized light of aportion of the urethane using a microscope equipped with a programmablehot stage is completed using a heating rate of 10° C. per minute and arange of 30° C. to 210° C. A melt temperature (T_(m)) of 180° C. isobserved followed by isotropization (T_(i)) at 199.6° C. Cooling of thesample followed by a repeat of the aforementioned heating cyclereplicates the observed Tm and T_(i) values. Stirring of the sample asit cools from T_(i) induces observable opalescence. Differentialscanning calorimetry of a portion of the urethane using a heating rateof 20° C. per minute and a range of 30° C. to 190° C. reveals a singleendotherm at 180° C. Cooling of the sample followed by a second heatingcycle at a rate of 5° C. per minute and a range of 30° to 200° C.reveals the following sequence of T_(m) to liquid crystal to T_(i)transitions:

    ______________________________________                                                      Temperature                                                                              Enthalpy                                             Event         (°C.)                                                                             (Kcal/mole)                                          ______________________________________                                        Endotherm     185.8      8.18                                                 Endotherm     189.0      1.68                                                 ______________________________________                                    

Deconvolution is used to resolve the enthalpies associated with theabove thermal transitions. Cooling of the sample at a rate of 5° C. perminute and at a range of 200° C. to 140° C. reveals exothermictransitions at 155.4° C. and 152.2° C. which are not well enoughresolved for measurement of the respective enthalpies. Cooling of thesample followed by a repeat of the conditions used for the secondheating cycle generally reproduces the previously observed endothermsbut overall enthalpy is decreased due to thermally induced decompositionof the urethane.

C. Propoxylation of the Epoxy Resin Adduct Prepared by the Reaction ofp-Phenylphenol and the Diglycidyl Ether of 4,4'-Dihydroxybiphenyl

A portion of the epoxy resin adduct (65.0 grams, 0.20 hydroxylequivalent) from A. above, propylene oxide (35.47 grams, 0.61 mole),1,4-dioxane (35.47 grams) and potassium hydroxide (0.10 gram, 1000 ppm)are added to a thick walled, preweighed, glass reactor which is thensealed and placed into a rotating steam heated autoclave. The autoclaveis heated to 120° C. and held at this reaction temperature for 34 hours,after which time the recovered product weight is determined to be 85.65grams (excluding KOH catalyst). The product is recovered by dissolutionin chloroform (200 milliliters). The chloroform solution is added to aseparatory funnel and washed with deionized water (75 milliliters). Therecovered chloroform extract is filtered through a bed of anhydroussodium sulfate followed by rotary evaporation of the dry filtrate undervacuum at 120° C. for 60 minutes. The propoxylate of the reactionproduct of p-phenylphenol and the diglycidyl ether of4,4'-dihydroxybiphenyl is recovered as a tacky, transparent, lightyellow colored solid (83.35 grams). Theoretical calculation (based ontheoretical hydroxyl content in the reaction product precursor and massbalance of the propoxylation) indicates that the addition of 1.74propylene oxide units per hydroxyl group contained in the reactionproduct precursor has occurred. Gel permeation chromatographic analysisusing glycerine polypropoxylates as calibration standards revealed aweight average molecular weight of 529 for the product, excluding a pairof minor shoulder peaks in the molecular weight calculation.

D. Synthesis of an Isocyanate Terminated Prepolymer Containing thePropoxylate of the Epoxy Resin Adduct (11.72 weight percent)

A portion of the propoxylate of the reaction product of p-phenylphenoland the diglycidyl ether of 4,4'-dihydroxybiphenyl (76.18 grams, 11.72weight percent) from C. above, a propylene glycol polypropoxylate havingan average molecular weight of 2000 (110.69 grams, 17.03 weightpercent), a glycerine polypropoxylate capped with 18 percent ethyleneoxide having an average molecular weight 4850 (280.30 grams, 43.12weight percent) and 4,4'-diisocyanatodiphenyl methane (182.84 grams,28.13 weight percent) are reacted as described in Example 1. Titrationof portions of the transparent, light yellow colored prepolymer revealsthe presence of 6.44 percent isocyanate, as compared with a theoreticalisocyanate amount of 6.5 percent.

E. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.1 grams) from D.above is added to an oven dried glass reactor and processed as describedin Example 1. A liquid chain extender (155.73 grams) is injected intothe reactor. The liquid chain extender solution is prepared by mixingmethylenebis(orthochloroaniline) (87.21 grams), propylene glycolpolypropoxylate having an average molecular weight of 2000 (52.33 grams)and glycerine polypropoxylate capped with 18 percent ethylene oxidehaving an average molecular weight of 4850 (78.49 grams) as described inExample 1 including use of a bismuth neodecanoate catalyst. Polyurethaneelastomer castings are prepared as described in Example 1 and testing oftheir physical and mechanical properties is done as described therein.The results are reported in Table 1.

EXAMPLE 6 - COMPARATIVE A. Synthesis of a Standard Isocyanate TerminatedPrepolymer Containing No Epoxy Resin Adduct

A portion of a propylene glycol polypropoxylate having an averagemolecular weight of 2000 (294.86 grams, 29.49 weight percent), aglycerine polyproxylate capped with 18 percent ethylene oxide having anaverage molecular weight of 4850 (442.28 grams, 44.23 weight percent)and 4,4'-diisocyanatodiphenyl methane (262.86 grams, 26.29 weightpercent) are added to an oven dried glass reactor and heated withstirring to 80° C. under a dry nitrogen atmosphere. After two hours ofreaction at the 80° C. temperature the transparent, colorless prepolymerliquid is recovered as a homogeneous solution and stored in a metal canunder a dry nitrogen atmosphere. Twenty-two hours later titration ofportions of the prepolymer reveals the presence of 6.685 percentisocyanate, as compared with a theoretical isocyanate amount of 6.5percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.1 grams) from A.above is added to an oven dried glass reactor as described in Example 1.A liquid chain extender (161.76 grams) is injected into the reactor. Theliquid chain extender solution is prepared by mixingmethylenebis(ortho-chloroaniline) (90.58 grams), propylene glycolpolypropoxylate having an average molecular weight of 2000 (54.35 grams)and glycerine polypropoxylate capped with 18 percent ethylene oxidehaving an average molecular weight of 4850 (81.52 grams) as described inExample 1 including use of a bismuth neodecanoate catalyst. Polyurethaneelastomer castings are prepared as described in Example 1 and testing oftheir physical and mechanical properties is done as described therein.The results are reported in Table 1.

                                      TABLE I                                     __________________________________________________________________________                SAMPLE DESIGNATION                                                                                          Example 6 -                         PROPERTY TESTED*                                                                          Example 1                                                                           Example 2                                                                           Example 3                                                                           Example 4                                                                           Example 5                                                                           Comparative                         __________________________________________________________________________    Specific Gravity                                                                          1.1025                                                                              1.1455                                                                              1.0960                                                                              1.1255                                                                              1.1391                                                                              1.1186                              Shore A Hardness                                                                          85    >90   84    88    85    85                                                    (Shore                                                                        D = 41)                                                     Bashore Rebound (%)                                                                       36    33    40    39    35    44                                  Die C Tear (lb./in.)                                                                      274   311   253   326   288   252                                             (6.5) (5.2) (21.9)                                                                              (12.1)                                                                              (6.0) (15.3)                              Split Tear (lb./in.)                                                                      78    126   75    123   65    73                                              (2.7) (15.7)                                                                              (8.9) (13.8)                                                                              (3.6) (8.2)                               Water Absorption                                                              regular (%) 2.69 (.06)                                                                          2.61 (.09)                                                                          2.81 (.01)                                                                          2.97 (.03)                                                                          2.25 (.01)                                                                          3.42 (.01)                          predried (%)                                                                              NA    2.80 (.02)                                                                          3.28 (.02)                                                                          3.01 (.03)                                                                          2.92 (.02)                                                                          3.53 (.03)                          Compression Set,                                                                          2.30  3.82  3.08  1.90  3.90  2.87                                Method B, 25° C./25%                                                   Flexural Modulus (psi)                                                                    7233  8535  6046  8519  7119  7326                                            (173) (171) (107)  (93) (127)  (90)                               Tensile Properties:                                                           Final Strain (%)                                                                          361 (34)                                                                            259 (9)                                                                             325 (16)                                                                            415 (25)                                                                            280 (21)                                                                            313 (54)                            Final Stress (psi)                                                                        2880 (186)                                                                          3646 (117)                                                                          2512 (194)                                                                          3552 (138)                                                                          2702 (188)                                                                          1891 (224)                          Stress (psi) at set                                                           strain:                                                                       5%          363 (13)                                                                            493 (41)                                                                            309 (12)                                                                            408 (13)                                                                            361 (8)                                                                             376 (13)                            50%         778 (10)                                                                            1065 (25)                                                                           748 (7)                                                                             849 (7)                                                                             858 (17)                                                                            733 (9)                             100%        1018 (23)                                                                           1456 (32)                                                                           1004 (14)                                                                           1137 (14)                                                                           1171 (36)                                                                           939 (15)                            200%        1552 (67)                                                                           2549 (66)                                                                           1557 (29)                                                                           1695 (31)                                                                           1927 (99)                                                                           1333 (39)                           __________________________________________________________________________     *Parenthetical () values designate the standard deviation.               

EXAMPLE 7 Dynamic Mechanical Thermal Analysis of Polyurethane ElastomerCastings

Portions (1.75 by 0.5 by 0.1 inch) of the elastomer castings of Examples2 and 4 and Comparative Example 6 are subjected to dynamic mechanicalthermal analysis (DMTA) using a Polymer Labs instrument in the threepoint bending mode. A 4° C. per minute rate of heatup is employed with atemperature range of -100° C. to 200° C. The deformation frequency usedis one Hertz. Storage modulus (E') values thus determined are given inTable II as a function of selected temperatures. The temperatures forobserved tan delta transitions are also given in Table II.

                                      TABLE II                                    __________________________________________________________________________    SAMPLE TAN DELTA                                                              DESIGNA-                                                                             TRANSITION                                                                            STORAGE MODULUS (dynes/cm.sup.2 × 10.sup.9)              TION   (°C.)                                                                          -100° C.                                                                    -50° C.                                                                     -25° C.                                                                     0° C.                                                                     25° C.                                                                     50° C.                                                                     100° C.                                                                    150° C.                                                                    200° C.               __________________________________________________________________________    Example 2                                                                            -16° C.                                                                        16.1 14.7 9.3  2.1                                                                              .56 .28 .10 .05 .15                                 (shoulder),                                                                     8° C.                                                         Example 4                                                                            -27° C.,                                                                       24.3 28.8 7.1  1.3                                                                              .54 .32 .12 .09 .11                                  132° C.                                                        Comparative                                                                          -30° C.,                                                                       21.4 21.4 1.9  .65                                                                              .37 .27 .16 .12 .21                          Example 6                                                                             159° C.                                                        __________________________________________________________________________

EXAMPLE 8 A. Wide Angle X-ray Scattering Analysis of PolyurethaneElastomer Castings

Two-inch by two-inch portions of the polyurethane elastomer castings ofExample 2 and Example 4 and Comparative Example 6 are analyzed for wideangle X-ray scattering using an X-ray pinhole camera. Copper K alphaX-rays are pinhole collimated and projected as a 0.5 millimeter squarebeam onto the surface of each respective casting sample. Each respectivesample is analyzed while under a tensile strain of 100 percent and then250 percent. The reflected X-rays are collected on a piece of filmlocated 5 centimeters above each sample. The observations made at bothof the applied tensile strains are summarized in Table III wherein theterm "oriented" refers to the presence of anisotropic scattering.

                  TABLE III                                                       ______________________________________                                        Sample   Amorphous Soft  Crystalline Hard                                     Designation                                                                            Segment Phase   Segment Phase                                        ______________________________________                                        Example 2                                                                              Amorphous peak  No peak present                                               oriented along                                                                equatorial line of film at                                                    4.27 angstroms at 100%                                                        strain, increased                                                             orientation at 250%                                                           strain                                                               Example 4                                                                              Amorphous peak  Crystalline peak                                              oriented along  oriented along                                                equatorial line of film at                                                                    equatorial line of film at                                    4.48 angstroms at 100%                                                                        6.07 angstroms at 100%                                        strain, increased                                                                             strain, no longer visible                                     orientation at 250%                                                                           at 250% strain                                                strain                                                               Comparative                                                                            Non-oriented broad                                                                            Crystalline peak                                     Example 6                                                                              peak at 4.27 angstroms                                                                        oriented along                                                for both % strains                                                                            equatorial line of film at                                                    5.3 angstroms for both                                                        % strains                                            ______________________________________                                    

EXAMPLE 9

RIM Processed Polyurethane Elastomer Prepared from an Epoxy Resin AdductPrepared by the Reaction of p-Phenylphenol and Diglycidyl Ether ofBisphenol A

A. Preparation of "A" Side Component

A portion (414.50 grams, 20.0% by weight) of the epoxy resin adductprepared from p-phenylphenol and the diglycidyl ether of bisphenol Ausing the method of Example 4 (0.05% residual epoxide) and4,4'-diisocyanatodiphenyl methane (1658.0 grams, 80.0% by weight) areadded to an oven dried glass reactor and heated to a 80° C. reactiontemperature with stirring under a nitrogen atmosphere. After 60 minutesat the 80° C. reaction temperature, the solution (2065.5 grams) isdiluted with carbodiimide modified 4,4'-diisocyanatodiphenyl methane(available from The Dow Chemical Co. as ISONATE* 143L) (1377.0 grams,40% by weight) and the resultant light yellow colored prepolymersolution is recovered and stored under nitrogen. Titration of a portionof the blended isocyanate prepolymer solution reveals the presence of26.64 percent isocyanate, as compared with a theoretical isocyanateamount of 26.2 percent.

B. Preparation of "B" Side Component

Ethylene glycol (700.0 grams, 83.3% by weight) and urea (140.0 grams,16.7% by weight) are combined and stirred with heating to 50° C. toprovide a solution. The ethylene glycol/urea solution is added to aglycerine polypropoxylate (prepared by capping a 3970 average molecularweight glycerine polypropoxylate with 19.6 percent ethylene oxide to a1630.8 hydroxyl equivalent weight) (4666.67 grams) to give a solutionwith a 216.7 hydroxyl equivalent weight. Immediately prior to use in thepreparation of a RIM processed elastomer, the "B" side solution iscatalyzed by mixing in 0.2% by weight dibutyltin dilaureate.

C. Preparation of RIM Processed Polyurethane Elastomer

The "A" side and "B" side components are loaded into the respectivereservoirs of a reactive injection molding (RIM) machine (Hi Tech MiniRIM, Hi Tech Engineering, Inc., Grand Rapids, Mich., Machine No. 2012)and heated to 110° F. The metal mold for making 6 inch by 6 inch by 1/10inch plaques is preheated to 160° F. A 30 second demold time is usedfollowed by postcuring of the plaques for 60 minutes at 250° F. The "B"side to "A" side ratio is 1.349 with an isocyanate index of 1.02. Thephysical and mechanical properties of the plaques is evaluated using themethods of Example 1. The results are reported in Table IV.

EXAMPLE 10 - Comparative RIM Processed Polyurethane Elastomer Preparedwithout an Epoxy Resin Adduct A. Preparation of "A" Side Component

Dipropylene glycol (92.05 grams, 6.0% by weight), tripropylene glycol(92.05 grams, 6.0% by weight) and 4,4'-diisocyanatodiphenyl methane(1350.0 grams, 88% by weight) are added to an oven dried glass reactorand heated to a 80° C. reaction temperature with stirring under anitrogen atmosphere. After 60 minutes at the 80° C. reactiontemperature, the prepolymer solution (1525.3 grams) is diluted withcarbodiimide modified 4,4'-diisocyanatodiphenyl methane (available fromThe Dow Chemical Co. as Isonate* 143L) (1016.87 grams, 40% by weight)and the resultant light amber colored solution is recovered and storedunder nitrogen. Titration of a portion of the blended isocyanateprepolymer solution reveals the presence of 25.29 percent isocyanate, ascompared with a theoretical isocyanate amount of 25.3 percent.

B. Preparation of RIM Processed Polyurethane Elastomer

The "A" side component described above and the "B" side componentdescribed in Example 9 are used to prepare reactive injection moldedplaques according to the method of Example 9, except the "B" side to "A"side ratio is 1.282. The resultant plaques are evaluated for physicaland mechanical properties using the method of Example 1. The results aregiven in Table IV.

                  TABLE IV                                                        ______________________________________                                                    Sample Designation                                                                        Example 10-                                           Property Tested*                                                                            Example 9 Comparative                                                                              Example 11                                 ______________________________________                                        Specific Gravity                                                                            0.9596    0.9810     1.0180                                     Shore A Hardness                                                                            92        90         91                                         Shore D Hardness                                                                            43        40         50                                         Bashore Rebound (%)                                                                         34        35         36                                         Die C Tear Strength                                                                         436       332        472                                        (lb./in.)     [6.2]     [6.5]      [1.1]                                      Split Tear Strength                                                                         160       113        174                                        (lb./in.)     [7.5]     [8.7]      [2.1]                                      Compression Set.,                                                                           4.63      3.47       3.69                                       Method B, 25° C./25%                                                   Flexural Modulus (psi)                                                                      14,428    10,215     7743                                                     [247]     [369]      [113]                                      Tensile Properties:                                                           Final Strain (%)                                                                            293       252        290                                                       [10]      [11]       [15]                                      Final Stress (psi)                                                                          3225      2818       2999                                                     [156]     [238]      [188]                                      Stress (psi) at set strain:                                                   5%            516       244        325                                                       [33]      [36]       [12]                                      50%           1258      1094       1155                                                      [14]      [55]       [13]                                      100%          1645      1514       1587                                                      [19]      [76]       [14]                                      200%          2440      2360       2302                                                      [22]     [118]       [21]                                      Percent Hard Segment.sup.1                                                                  44.4      45.3       41.1                                       ______________________________________                                         *[ ]values designate the standard deviation.                                  .sup.1 Weight ethylene glycol + weight diisocyanate reacting with ethylen     glycol divided by total weight.                                          

EXAMPLE 11 RIM Processed Polyurethane Elastomer Containing an EpoxyResin Adduct Prepared by the Reaction of p-Phenylphenol and DiglycidylEther of Bisphenol A Plus a Mesogenic Diisocyanat A. Preparation of "A"Side Component

4,4'-Diisocyanatodiphenyl methane (1800.0 grams, 90.0% by weight) and3.3'-dimethyl-4,4'-diisocyanatodiphenyl (200.0 grams, 10.0% by weight)are added to an oven dried glass reactor and heated to 100° C. withstirring under a nitrogen atmosphere. The heated mixture is diluted withcarbodiimide modified 4,4'-diisocyanatodiphenyl methane (1333.33 grams,40% by weight of the total solution), then stirred under the nitrogenatmosphere with heating until the 100° C. temperature is reached again.The resultant light yellow colored solution is recovered and storedunder nitrogen. Titration of a portion of the blended isocyanatesolution reveals the presence of 32.03 percent isocyanate, as comparedwith a theoretical isocyanate amount of 31.76 percent.

B. Preparation of "B" Side Component

Ethylene glycol (450.0 grams, 83.3% by weight) and urea (90.0 grams,16.7% by weight) are combined and stirred with heating to 50° C. Theethylene glycol/urea solution is added to glycerine polypropoxylate(prepared by capping a 3970 average molecular weight glycerinepolypropoxylate with 19.6 percent ethylene oxide to a 1630.8 hydroxylequivalent weight) (2850.0 grams). A portion (150.0 grams, 4.24% byweight of the total solution) of the epoxy resin adduct of Example 4(0.05% residual epoxide) is ground to a powder then added to thepolyol/ethylene glycol/urea solution. The solution is heated under anitrogen atmosphere with stirring to form a solution with a 217.01hydroxyl equivalent weight and a density of 1.0481 at 25° C. Immediatelyprior to use in the preparation of a RIM processed elastomer, the "B"side solution is catalyzed by mixing in 0.2% by weight dibutyltindilaureate.

C. Preparation of RIM Processed Polyurethane Elastomer

The "A" and "B" side components are loaded into the respectivereservoirs of a reactive injection molding (RIM) machine using themethod and conditions of Example 9. The "B" side to "A" side ratio is1.622 with an isocyanate index of 1.02. The physical and mechanicalproperties of the plaques are evaluated using the methods of Example 1.The results are reported in Table IV.

EXAMPLE 12 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (6.88 weight percent) Prepared byReacting p-Phenylphenol and Diglycidyl Ether of Bisphenol A Plus aMesogenic Diisocyanate (3.90 weight percent) and Poly(tetramethyleneglycol) as the Polyol

A portion of an epoxy resin adduct prepared by reacting p-phenylphenoland the diglycidyl ether of bisphenol A (68.79 grams, 6.88 weightpercent), according the method of Example 1, (0.01% residual epoxide),poly(tetramethylene glycol) having a hydroxyl equivalent weight of1013.11 (619.13 grams, 61.91 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (39.01 grams, 3.90 weightpercent) and 4,4'-diisocyanatodiphenyl methane (273.07 grams, 27.31weight percent) are added to an oven dried glass reactor and heated withstirring to 80° C. under a dry nitrogen atmosphere After three hours ofreaction at the 80° C. temperature, the transparent prepolymer liquid isrecovered as a homogeneous solution and stored in a metal can under adry nitrogen atmosphere. Twenty four hours later, titration of portionsof the prepolymer reveals the presence of 7.13 percent isocyanate, ascompared with a theoretical isocyanate amount of 7.0 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (399.3 grams) from A.is added to an oven dried glass reactor and heated with stirring to 50°C. prepolymer under a vacuum of 1 millimeter of Hg or less. After 2hours the prepolymer was cooled to 24° C., stirring was stopped, thevacuum was released, then 179.93 grams of a liquid chain extendersolution is injected into the reactor. The liquid chain extendersolution is prepared by mixing methylenebis(orthochloroaniline) (71.97grams) and poly(tetramethylene glycol) having a hydroxyl equivalentweight of 1013.11 (107.96 grams) at 110° C. with stirring for 20minutes, followed by degassing at 65° C. under vacuum for 60 minutes.Polyurethane elastomer castings are prepared as described in Example 1including use of a bismuth neodecanoate catalyst and testing of theirphysical and mechanical properties is done as described therein. Theresults are reported in Table V.

EXAMPLE 13 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (6.86 weight percent) Prepared byReacting of p-Phenylphenol and Diglycidyl Ether of Bisphenol A Plus aMesogenic Diisocyanate (7.85 weight percent) and Poly(tetramethyleneglycol) as the Polyol

A portion of a reaction product of p-phenylphenol and the diglycidylether of bisphenol A (68.61 grams, 6.86 weight percent) prepared usingthe method of Example 1, (0.01% residual epoxide), poly(tetramethyleneglycol having a hydroxyl equivalent weight of 1013.11 (617.47 grams,61.75 weight percent), 3,3'-dimethyl-4,4'-diisocyanatodiphenyl (78.48grams, 7.85 weight percent) and 4,4'-diisocyanatodiphenyl methane(235.44 grams, 23.54 weight percent) are used to prepare a prepolymer asdescribed in Example 12. Titration of portions of the transparentprepolymer revealed the presence of 6.97 percent isocyanate, as comparedwith a theoretical isocyanate amount of 7.0 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.1 grams) from A.above is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (176.18 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (70.47 grams) andpoly(tetramethylene glycol) having a hydroxyl equivalent weight of1013.11 (105.71 grams) at 110° C. with stirring for 20 minutes followedby degassing at 65° C. under vacuum for 60 minutes. Polyurethaneelastomer castings are prepared as described in Example 1 including useof a bismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table V.

EXAMPLE 14 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (13.44 weight percent) Prepared byReacting p-Phenylphenol and the Diglycidyl Ether of Bisphenol A Plus aMesogenic Diisocyanate (8.21 weight percent) and Poly(tetramethyleneglycol) as the Polyol

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (134.36 grams, 13.44 weight percent) prepared usingthe method of Example 1, (0.01% residual epoxide), poly(tetramethyleneglycol having a hydroxyl equivalent weight of 1013.11 (537.46 grams,53.75 weight percent), 3,3'-dimethyl-4,4'-diisocyanatodiphenyl (82.05grams, 8.21 weight percent) and 4,4'-diisocyanatodiphenyl methane(246.14 grams, 24.61 weight percent) are used to prepare a prepolymer asdescribed in Example 12. Titration of portions of the prepolymerrevealed the presence of 6.99 percent isocyanate, as compared with atheoretical isocyanate amount of 7.0 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.0 grams) from A.above is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (176.76 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (70.70 grams) andpoly(tetramethylene glycol) having a hydroxyl equivalent weight of1013.11 (106.06 grams) as described in Example 13. Polyurethaneelastomer castings are prepared as described in Example 1 including useof a bismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table V.

EXAMPLE 15 - COMPARATIVE

A. Synthesis of an Isocyanate Terminated Prepolymer ContainingPoly(tetramethylene glycol) as the Polyol Without Using an Epoxy ResinAdduct

Poly(tetramethylene glycol) having a hydroxyl equivalent weight of1013.11 (704.52 grams, 70.45 weight percent) and4,4'-diisocyanatodiphenyl methane (295.48 grams, 29.55 weight percent)are added to an oven dried glass reactor and heated with stirring to 80°C. under a dry nitrogen atmosphere. After three hours of reaction at the80° C. temperature, the transparent prepolymer liquid is recovered as ahomogeneous solution and stored in a metal can under a dry nitrogenatmosphere. Titration of portions of the prepolymer reveals the presenceof 7.02 percent isocyanate, as compared with a theoretical isocyanateamount of 7.0 percent.

B. Preparation of a Standard Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.7 grams) from A.above is used to prepare polyurethane elastomer castings as described inExample 12. A liquid chain extender solution (177.69 grams) is injectedinto the reactor. The liquid chain extender solution is prepared bymixing methylenebis(ortho-chloroaniline) (71.08 grams) andpoly(tetramethylene glycol) having a hydroxyl equivalent weight of1013.11 (106.61 grams) as described in Example 13. Polyurethaneelastomer castings are prepared as described in Example 1 including useof a bismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table V.

EXAMPLE 16 - COMPARATIVE A. Synthesis of an Isocyanate TerminatedPrepolymer Prepared from a Poly(tetramethylene glycol) Blend (1013.11and 303.59 hydroxyl equivalent weights) Without Using an Epoxy ResinAdduct

Poly(tetramethylene glycol having a hydroxyl equivalent weight of1013.11 (628.07 grams, 62.81 weight percent), poly(tetramethyleneglycol) having a hydroxyl equivalent weight of 303.59 (60.83 grams, 6.08weight percent) and 4,4'-diisocyanatodiphenyl methane (311.10 grams,31.11 weight percent) are added to an oven dried glass reactor andheated with stirring to 80° C. under a dry nitrogen atmosphere. Afterthree hours of reaction at the 80° C. temperature, the transparentprepolymer liquid was recovered as a homogeneous solution and stored ina metal can under a dry nitrogen atmosphere. Twenty four hours later,titration of portions of the prepolymer revealed the presence of 7.02percent isocyanate, as compared with a theoretical isocyanate amount of7.0 percent.

B. Preparation of a Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.1 grams) from A.above is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender is injected into the reactor(177.59 grams). The liquid chain extender is prepared by mixingmethylenebis(ortho-chloroaniline) (71.04 grams) and poly(tetramethyleneglycol) having a hydroxyl equivalent weight of 1013.11 (106.55 grams) asdescribed in Example 13. Polyurethane elastomer castings are prepared asdescribed in Example 1 including use of a bismuth neodecanoate catalystand testing of their physical and mechanical properties is done asdescribed therein. The results are reported in Table V.

EXAMPLE 17 - COMPARATIVE A. Synthesis of an Isocyanate TerminatedPrepolymer Prepared from Poly(tetramethylene glycol) as the Polyol and aMesogenic Diisocyanate (5.18 weight percent), Without Using an EpoxyResin Adduct

Poly(tetramethylene glycol having a hydroxyl equivalent weight of1013.11 (700.94 grams, 70.09 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (74.77 grams, 7.48 weightpercent) and 4,4'-diisocyanatodiphenyl methane (224.30 grams, 22.43weight percent) are added to an oven dried glass reactor and processedas described in Example 16. Titration of portions of the slightly hazyprepolymer reveals the presence of 7.03 percent isocyanate, as comparedwith a theoretical isocyanate amount of 7.0 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer (400.0 grams) from A.above is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender (177.76 grams) is injected intothe reactor. The liquid chain extender is prepared by mixingmethylenebis(ortho-chloroaniline) (71.10 grams) and poly(tetramethyleneglycol) having a hydroxyl equivalent weight of 1013.11 (106.65 grams) asdescribed in Example 13. Polyurethane elastomer castings are prepared asdescribed in Example 1 including use of a bismuth neodecanoate catalystand testing of their physical and mechanical properties is done asdescribed therein. The results are reported in Table V.

                                      TABLE V                                     __________________________________________________________________________                  Example        Comparative Example                              Property Tested*                                                                            12   13   14   15   16   17                                     __________________________________________________________________________    Specific Gravity                                                                            1.0895                                                                             1.0981                                                                             1.1129                                                                             1.0843                                                                             1.0918                                                                             1.0631                                 Shore A Hardness                                                                            91   89   94   86   89   88                                     Bashore (%)   45   46   42   49   46   45                                     Die C Tear (lb./in.)                                                                        505  510  529  507  478  491                                                  [9.9]                                                                              [6.9]                                                                              [5.7]                                                                              [6.7]                                                                              [15.3]                                                                             [6.7]                                  Split Tear (lb./in.)                                                                        157  195  252  150  157  153                                                  [3.3]                                                                              [18.7]                                                                             [3.3]                                                                              [21.9]                                                                             [6.7]                                                                              [51]                                   Water Absorption                                                              Regular (%)   1.28 1.14 1.01 1.19 1.34 1.60                                                 [0.05]                                                                             [0.09]                                                                             [0.01]                                                                             [0.01]                                                                             [0.04]                                                                             [0.02]                                 Predried (%)  1.59 1.55 1.11 1.62 1.71 1.67                                                 [0.04]                                                                             [0.01]                                                                             [0.04]                                                                             [0.02]                                                                             [0.01]                                                                             [0.00]                                 Compression Set, Method B                                                                   5.99 7.54 3.32 4.15 4.28 3.60                                   25° C./25%                                                             Flexural Modulus (psi)                                                                      12,392                                                                             13,346                                                                             16,494                                                                             12,721                                                                             12,430                                                                             10,822                                               [649]                                                                              [342]                                                                              [272]                                                                              [475]                                                                              [444]                                                                              [134]                                  Tensile Properties:                                                           Final Strain (%)                                                                            615  637  458  615  622  609                                                   [41]                                                                               [56]                                                                               [6] [113]                                                                               [41]                                                                               [11]                                  Final Stress (psi)                                                                          5907 5564 5047 3933 4154 3967                                                 [405]                                                                              [264]                                                                              [128]                                                                              [517]                                                                              [290]                                                                              [174]                                  Stress (psi) at set strain:                                                   5%            660  563  786  571  589  402                                                   [60]                                                                               [19]                                                                               [21]                                                                               [29]                                                                               [45]                                                                               [39]                                  50%           1066 1056 1151 982  1014 825                                                   [78]                                                                               [63]                                                                               [19]                                                                               [48]                                                                               [18]                                                                               [8]                                   100%          1283 1266 1427 1182 1208 1013                                                 [107]                                                                               [84]                                                                               [28]                                                                               [68]                                                                               [35]                                                                               [8]                                   200%          1796 1726 2116 1527 1537 1351                                                 [166]                                                                              [133]                                                                               [79]                                                                              [131]                                                                               [62]                                                                               [18]                                  300%          2747 2648 3761 2079 2103 1852                                                 [392]                                                                              [227]                                                                              [222]                                                                              [295]                                                                              [120]                                                                               [12]                                  Percent Hard Segment.sup.1                                                                  18.21                                                                              18.09                                                                              18.12                                                                              18.07                                                                              18.07                                                                              18.17                                  __________________________________________________________________________     *Bracketed [ ] values designate the standard deviation.                       .sup.1 weight methylenebis(orthochloroaniline) + weight diisocyanate(s)       reacting with methylenebis(orthochloroaniline) divided by total weight.  

EXAMPLE 18 Abrasion Resistance Testing of Polyurethane Elastomers

Portions of the polyurethane elastomer castings from Example 13 andComparative Example 16 are evaluated for resistance to Taber abrasionusing a Teledyne Taber Dual Abraser (Model 505) with standard methods(ASTM D 1044). Testing is completed using a H-18 wheel and 1000 cycles.The results are reported in Table VI.

                  TABLE VI                                                        ______________________________________                                        Designation Loss/1000  Weight loss as percent                                 of Sample   Cycles (mg)                                                                              of original weight                                     ______________________________________                                        Example 13  20.0       0.0925                                                 Comparative 63.5       0.2756                                                 Example 16                                                                    ______________________________________                                    

EXAMPLE 19 A. Synthesis of an Isocyanate Terminated PrepolymerContaining an Epoxy Resin Adduct (6.17 weight percent) Prepared byReacting p-Phenylphenol and Diglycidyl Ether of Bisphenol A

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (61.73 grams, 6.17 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide, 4.9% hydroxyl), a blockcopolymer of polyethylene glycol with 1,2-butylene oxide having ahydroxyl equivalent weight of 899 (555.55 grams, 55.56 weight percent)and 4,4'-diisocyanatodiphenyl methane (382.72 grams, 38.27 weightpercent) are added to an oven dried glass reactor and heated withstirring to 80° C. under a dry nitrogen atmosphere. The block copolymerof polyethylene glycol and 1,2-butylene oxide used herein is preparedvia copolymerization of 1000 weight average molecular weightpolyethylene glycol as a partial potassium alkoxide with 1,2-butyleneoxide to a 1798 weight average molecular weight, followed byneutralization and removal of salt. After three hours at 80° C. thetransparent, light yellow colored prepolymer is recovered as ahomogeneous liquid and stored in a metal can under a dry nitrogenatmosphere. Twenty four hours later, titration of portions of theprepolymer reveals the presence of 9.56 percent isocyanate, as comparedwith a theoretical isocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from B. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (236.73 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (94.69 grams) and ablock copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(142.04 grams) at 110° C. for twenty minutes, followed by degassingunder vacuum at 50° C. for sixty minutes. Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst testing of their physical and mechanicalproperties is done as described therein. The results are reported inTable VII.

EXAMPLE 20 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (6.13 weight percent) Prepared by theReaction of p-Phenylphenol and Diglycidyl Ether of Bisphenol A PlusMesogenic Diisocyanate (9.68 weight percent)

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (61.28 grams, 6.13 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide, 4.9% hydroxyl), thepolyol used in Example 19 (551.53 grams, 55.16 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (96.80 grams, 9.68 weightpercent) and 4,4'-diisocyanatodiphenyl methane (290.39 grams, 29.39weight percent) are used to prepare a prepolymer as described in Example19. Titration of portions of the transparent, light yellow coloredprepolymer reveals the presence of 9.76 percent isocyanate, as comparedwith a theoretical isocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (241.58 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (96.63 grams) andblock copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(144.95 grams) as described in Example 19. Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table VII.

EXAMPLE 21 - COMPARATIVE A. Synthesis of an Isocyanate TerminatedPrepolymer Prepared Without an Epoxy Resin Adduct

The polyol used in Example 19 (629.47 grams, 62.95 weight percent) and4,4'-diisocyanatodiphenyl methane (370.53 grams, 37.05 weight percent)are used to prepare a prepolymer as described in Example 19. Titrationof portions of the opaque, white prepolymer reveals the presence of 9.49percent isocyanate, as compared with a theoretical isocyanate amount of9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (235.02 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (94.01 grams) andblock copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(141.01 grams), as described in Example 19. Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table VII.

                  TABLE VII                                                       ______________________________________                                                  Sample Designation                                                                                    Comparative                                 Property Tested*                                                                          Example 19 Example 20 Example 21                                  ______________________________________                                        Specific Gravity                                                                            1.1675     1.1651     1.1585                                    Shore A Hardness                                                                           80         85         75                                         Bashore Rebound                                                                            20         29         18                                         (%)                                                                           Die C Tear   345 [6.7]  344 [4.0]  228 [2.9]                                  Strength (lb./in.)                                                            Split Tear Strength                                                                        116 [2.6]  212 [15.8]                                                                               95 [7.5]                                   (lb./in.)                                                                     Water Absorption                                                              Regular (%)   3.92 [.04]                                                                              11.46 [.23]                                                                              16.03 [.05]                                Predried (%)                                                                                4.52 [.03]                                                                              11.78 [.19]                                                                              16.46 [1.01]                               Compression Set,                                                                            2.93       3.62       2.82                                      Method B, 25° C./                                                      25%                                                                           Flexural Modulus                                                                          3210 [44]  8774 [32]  3165 [90]                                   (psi)                                                                         Flexural Strength                                                                          153 [2.1]  394 [5.4]  151 [3.8]                                  (psi)                                                                         Tensile Properties:                                                           Final Strain (%)                                                                           348 [5.6]  438 [21]   418 [7]                                    Final Stress (psi)                                                                        7226 [223] 2768 [61]  2555 [7]                                    Modulus (psi):                                                                50%          697 [29]   813 [19]   437 [19]                                   100%         974 [25]  1003 [18]   566 [24]                                   200%        1900 [29]  1386 [16]   835 [37]                                   300%        4308 [102] 1863 [8]   1280 [17]                                   Percent Hard                                                                               121.98     22.21      21.93                                      Segment.sup.1                                                                 ______________________________________                                         *Bracketed [ ] values designate the standard deviation.                       .sup.1 weight methylenebis(orthochloroaniline) + weight diisocyanate(s)       reacting with methylenebis(orthochloroaniline) divided by total weight.  

EXAMPLE 22 Accelerated Fatigue Testing of Precracked PolyurethaneElastomer Castings

Portions of the polyurethane elastomer castings of Examples 19 and 20and Comparative Example 21 are used for accelerated fatigue testing on aMTS 810 Material Test System with controller cartridges for strain ±50percent, load ±300 lbs. and displacement ±5 inches. Test pieces (2.5inches by 1 inch by 100 mils nominal) are prepared and then precracked1/16 inch from the edge toward the center using a sharp razor blade.Test conditions included the use of a 1 inch span, 5 Hz, 250 cycles andload control at ambient temperature (21° C.). Lower and upper loads arevaried systematically as shown in Table VIII for each repetitive set of250 cycles until failure occurs. Failure is observed as crackpropagation through the test piece in each test. The results aresummarized in Table VIII wherein the loadings are normalized to exactly100 mils of sample thickness.

                  TABLE VIII                                                      ______________________________________                                                        UPPER LOAD                                                                    (Lbs./100                                                     SAMPLE DESCRIPTION                                                                            mils)       Comments                                          ______________________________________                                        Example 19      13.1                                                                          18.5                                                                          21.2                                                                          25.1                                                                          31.1                                                                          32.3                                                                          35.1                                                                          39.1                                                                          44.5                                                                          49.5        (partially glassy,                                                            smooth break)                                     Example 20      36.3                                                                          41.5                                                                          46.2                                                                          49.2                                                                          53.6                                                                          57.0                                                                          60.5                                                                          62.2                                                                          64.8        (non-glassy, rough                                                            break)                                            Comparative                                                                   Example 21                                                                    (Run 1)         31.0                                                                          35.0                                                                          38.2        (glassy, smooth                                                               break)                                            (Run 2)         15.0                                                                          24.0                                                                          25.0                                                                          29.0                                                                          31.5                                                                          35.0                                                                          38.7        (glassy, smooth                                                               break)                                            ______________________________________                                    

EXAMPLE 23 Dynamic Mechanical Thermal Analysis of Polyurethane ElastomerCastings

Portions (1.75 by 0.5 by 0.1 inch) of the polyurethane elastomercastings of Examples 19 and 20 and Comparative Example 21 are subjectedto dynamic mechanical thermal analysis (DMTA) using a Polymer Labsinstrument in the three point bending mode. A 4° C. per minute rate ofheatup is employed with a temperature range of -100° C. to 200° C. Thedeformation frequency used is one Hertz. Storage modulus (E') valuesthus determined are given in Table IX as a function of selectedtemperatures. The temperatures for observed tan delta transitions arealso given in Table IX.

                                      TABLE IX                                    __________________________________________________________________________              Tan Delta                                                                     Transition                                                                          Storage Modulus (dynes/cm.sup.2 × 10.sup.9)             Sample Designation                                                                      (°C.)                                                                        -100° C.                                                                    -50° C.                                                                     -25° C.                                                                     0° C.                                                                     25° C.                                                                     50° C.                                                                     100° C.                                                                    150° C.                                                                    200° C.              __________________________________________________________________________    Example 19                                                                              18    7.99 8.80 8.52 5.84                                                                             .30 .11 .09 .08 .08                         Example 20                                                                              -2    7.03 7.26 7.64 1.52                                                                             .53 .33 .25 .23 .14                         Comparative                                                                              3    8.25 8.15 7.26 1.25                                                                             .17 .11 .09 .09 .09                         Example 21                                                                    __________________________________________________________________________

EXAMPLE 24 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (9.10 weight percent) Prepared by theReaction of p-Phenylphenol and Diglycidyl Ether of Bisphenol A PlusMesogenic Diisocyanate (9.83 weight percent)

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (91.03 grams, 9.10 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide, 4.9% hydroxyl), thepolyol used in Example 19 (515.84 grams, 51.58 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (98.28 grams, 9.83 weightpercent) and 4,4'-diisocyanatodiphenyl methane (294.85 grams, 29.48weight percent) are used to prepare a prepolymer as described in Example19. Titration of a portion of the slightly opaque, light yellow coloredprepolymer reveals the presence of 9.72 percent isocyanate, as comparedwith a theoretical isocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (240.59 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (96.24 grams) andthe block copolymer of polyethylene glycol and 1,2-butylene oxide (899HEW) (144.35 grams) as described in Example 18. Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table X.

                  TABLE X                                                         ______________________________________                                                          SAMPLE DESIGNATION                                          PROPERTY TESTED*      Example 19                                              ______________________________________                                        Specific Gravity         1.1709                                               Shore A Hardness         87                                                   Bashore Rebound (%)      25                                                   Die C Tear Strength (lb./in.)                                                                         373 (4.4)                                             Split Tear Strength (lb./in.)                                                                         215 (11.3)                                            Water Absorption                                                              Regular (%)              9.03 (.16)                                           Predried (%)             10.13 (.55)                                          Compression Set, Method B,                                                                             4.27                                                 25° C./25%                                                             Flexural Modulus (psi)                                                                              10,370 (198)                                            Flexural Strength (psi)                                                                               467 (28.5)                                            Tensile Properties:                                                           Final Strain (%)        341 (32)                                              Final Stress (psi)      3285 (349)                                            Modulus (psi):                                                                50%                     935 (12)                                              100%                    1193 (12)                                             200%                    1825 (20)                                             300%                    2787 (41)                                             Percent Hard Segment.sup.1                                                                             22.19                                                ______________________________________                                         *Parenthetical () values designate the standard deviation.                    .sup.1 weight methylenebis(orthochloroaniline) + weight diisocyanate(s)       reacting with methylenebis(orthochloroaniline) divided by total weight.  

EXAMPLE 25 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (6.42 weight percent) Prepared by theReaction of p-Phenylphenol and Diglycidyl ether of Bisphenol A PlusMesogenic Diisocyanate (8.96 weight percent) and a Polyol Mixture

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (64.16 grams, 6.42 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide, 4.9% hydroxyl), thepolyol used in Example 19 (230.97 grams, 23.1 weight percent), aglycerine polypropoxylate capped with 18 percent ethylene oxide having ahydroxyl equivalent weight of 1669.6 (346.46 grams),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (89.61 grams, 8.96 weightpercent) and 4,4'-diisocyanatodiphenyl methane (268.83 grams, 26.83weight percent) are used to prepare a prepolymer as described in Example19. Titration of a portion of the opaque, white prepolymer reveals thepresence of 9.60 percent isocyanate, as compared with a theoreticalisocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (250.23 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (100.09 grams),block copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(60.06 grams) and glycerine polypropoxylate (1669.6 HEW) (90.08 grams)described in Example 19. Polyurethane elastomer castings are prepared asdescribed in Example 1 including use of a bismuth neodecanoate catalystand testing of their physical and mechanical properties is done asdescribed therein. The results are reported in Table XI.

                  TABLE XI                                                        ______________________________________                                                          SAMPLE DESIGNATION                                          PROPERTY TESTED*      Example 7                                               ______________________________________                                        Specific Gravity         1.1508                                               Shore A Hardness         89                                                   Bashore Rebound (%)      36                                                   Die C Tear Strength (lb./in.)                                                                         376 (6.7)                                             Split Tear Strength (lb./in.)                                                                         146 (6.8)                                             Water Absorption                                                              Regular (%)              5.28 (.14)                                           Predried (%)             5.36 (.00)                                           Compression Set, Method B,                                                                             4.43                                                 25° C./25%                                                             Flexural Modulus (psi)                                                                              13,464 (895)                                            Flexural Strength (psi)                                                                               599 (37.5)                                            Tensile Properties:                                                           Final Strain (%)        340 (20.9)                                            Final Stress (psi)      3329 (203)                                            Stress (psi) at set strain:                                                   50%                     1048 (2)                                              100%                    1343 (8)                                              200%                    2032 (14)                                             300%                    2963 (24)                                             Percent Hard Segment.sup.1                                                                             22.18                                                ______________________________________                                         *Parenthetical () values designate the standard deviation.                    .sup.1 weight methylenebis(orthochloroaniline) + weight diisocyanate(s)       reacting with methylenebis(orthochloroaniline) divided by total weight.  

EXAMPLE 26 Dynamic Mechanical Thermal Analysis of Polyurethane ElastomerCastings

Portions of the polyurethane elastomer castings of Examples 24 and 25are subjected to dynamic mechanical thermal analysis (DMTA) using themethod of Example 23. The results are summarized in Table XII.

                                      TABLE XII                                   __________________________________________________________________________              Tan Delta                                                                     Transition                                                                          Storage Modulus (dynes/cm.sup.2 × 10.sup.9)             Sample Designation                                                                      (°C.)                                                                        -100° C.                                                                    -50° C.                                                                     -25° C.                                                                     0° C.                                                                     25° C.                                                                     50° C.                                                                     100° C.                                                                    150° C.                                                                    200° C.              __________________________________________________________________________    Example 24                                                                               -1   21.1 18.8 14.4 2.97                                                                             .87 .46 .34 .34 .19                         Example 25                                                                              -10   23.7 22.5 7.60 2.61                                                                             1.12                                                                              .68 .46 .37 .30                         __________________________________________________________________________

EXAMPLE 27 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (6.15 weight percent) Prepared by theReaction of p-Phenylphenol and Diglycidyl Ether of Bisphenol A PlusMesogenic Diisocyanate (4.81 weight percent)

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (55.36 grams, 6.15 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide 4.9% hydroxyl), thepolyol used in Example 19 (498.20 grams, 55.36 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (43.31 grams, 4.81 weightpercent) and 4,4'-diisocyanatodiphenyl methane (303.14 grams, 33.68weight percent) are used to prepare a prepolymer as described in Example19. Titration of a portion of the slightly opaque, light yellow coloredprepolymer reveals the presence of 9.59 percent isocyanate, as comparedwith a theoretical isocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (400.0grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (237.37 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (94.95 grams) andblock copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(142.42 grams) as described in Example 19. Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table XIII.

EXAMPLE 28 A. Synthesis of an Isocyanate Terminated PrepolymerContaining the Epoxy Resin Adduct (12.02 weight percent) Prepared by theReaction of p-Phenylphenol and Diglycidyl Ether of Bisphenol A PlusMesogenic Diisocyanate

A portion of the reaction product of p-phenylphenol and the diglycidylether of bisphenol A (120.21 grams, 12.02 weight percent) prepared usingthe method of Example 4 (0.05% residual epoxide, 4.9% hydroxyl), thepolyol used in Example 19. (480.83 grams, 48.08 weight percent),3,3'-dimethyl-4,4'-diisocyanatodiphenyl (99.74 grams, 9.97 weightpercent) and 4,4'-diisocyanatodiphenyl methane (299.22 grams, 29.92weight percent) are used to prepare a prepolymer as described in Example19. Titration of a portion of the slightly opaque, light yellow coloredprepolymer reveals the presence of 9.57 percent isocyanate, as comparedwith a theoretical isocyanate amount of 9.5 percent.

B. Preparation of Polyurethane Elastomer Casting

A portion of the isocyanate terminated prepolymer from A. above (402.4grams) is used to prepare a polyurethane elastomer casting as describedin Example 12. A liquid chain extender solution (238.41 grams) isinjected into the reactor. The liquid chain extender solution isprepared by mixing methylenebis(ortho-chloroaniline) (95.36 grams) andblock copolymer of polyethylene glycol and 1,2-butylene oxide (899 HEW)(143.05 grams) as described in Example 19 Polyurethane elastomercastings are prepared as described in Example 1 including use of abismuth neodecanoate catalyst and testing of their physical andmechanical properties is done as described therein. The results arereported in Table XIII.

                  TABLE XIII                                                      ______________________________________                                                       SAMPLE DESIGNATION                                             PROPERTY TESTED* Example 27  Example 28                                       ______________________________________                                        Specific Gravity   1.1658       1.1735                                        Shore A Hardness  84            90                                            Bashore Rebound (%)                                                                             17            25                                            Die C Tear Strength                                                                             344 [9.2]    415 [6.2]                                      (lb./in.)                                                                     Split Tear Strength                                                                             136 [2.8]    233 [9.4]                                      (lb./in.)                                                                     Water Absorption                                                              Regular (%)        9.40 [.29]                                                                                 7.63 [.25]                                    Predried (%)      10.49 [.08]                                                                                 7.65 [.21]                                    Compression Set, Method                                                                          7.63         11.14                                         B, 25° C./25%                                                          Flexural Modulus (psi)                                                                         5384 [186]  11,373 [269]                                     Flexural Strength (psi)                                                                         204 [5.3]    426 [5.6]                                      Tensile Properties:                                                           Final Strain (%)  353 [9]      378 [16]                                       Final Stress (psi)                                                                             4515 [300]    4383 [225]                                     Modulus (psi):                                                                50%               843 [0]      1036 [4]                                       100%             1105 [0]      1316 [44]                                      200%             1801 [0]      1950 [47]                                      Percent Hard Segment.sup.1                                                                      22.05         22.08                                         ______________________________________                                         *Bracketed [ ] values designate the standard deviation.                       .sup.1 weight methylenebis(orthochloroaniline) + weight diisocyanate(s)       reacting with methylenebis(orthochloroaniline) divided by total weight.  

What is claimed is:
 1. A polyurethane composition prepared from aformulation comprising:(1) an adduct prepared by reacting (a) a compoundcontaining at least one epoxy group per molecule with (b) a compoundcontaining at least one epoxide reactive group per molecule, whereinwhen compound (a) is a polyepoxide, compound (b) contains a singleepoxide reactive group per molecule, and when compound (a) is amonoepoxide, compound (b) contains at least two epoxide reactive groupsper molecule and said monoepoxide compound is a monoglycidyl ether, (2)a polyisocyanate; and (3) optionally, an isocyanate-reactive compoundwhich is different from component (1);wherein at least one of the adductor the polyisocyanate contains a rodlike mesogenic moiety.
 2. Thecomposition of claim 1 wherein the adduct contains at least one rodlikemesogenic moiety and the polyisocyanate is free of mesogenic moieties.3. The composition of claim 1 wherein the rodlike mesogenic moiety ispresent in the adduct is the main chain, a side chain, or both.
 4. Thecomposition of claim 2 wherein the compound containing at least oneepoxide-reactive group per molecule contains as the reactive group a--OH, --NHR³, --SH or --COOH group wherein R³ is hydrogen or ahydrocarbyl group having from 1 to about 12 carbon atoms.
 5. Thecomposition of claim 4 wherein the compound containing at least oneepoxy group per molecule is a polyepoxide and the compound containing atleast one epoxide reactive group per molecule contains a singleepoxide-reactive group.
 6. The composition of claim 1 wherein thepolyurethane is cellular or non-cellular.
 7. The composition of claim 1wherein the polyurethane is thermoplastic or thermoset.
 8. Thecomposition of claim 1 which has been oriented.
 9. The composition ofclaim 8 wherein the orientation is accomplished by means of theapplication of an electric field, a magnetic field, or drawing and/orshear forces.